It looks like L5R might be restarted, which is probably a good thing. It has been a fun ride having tournament outcomes decide everything, but many tournament wins have kind of prevented a lot of future options being viable. The timeline has gotten a little overcomplicated... so... maybe moving to a new AU Rokugan is a good thing.
A few changes I would make to the overall theme of the game....
First, muskets and arbequises should exist. It was the Europeans who said 'this weapon is below us' not the Japanese or Chinese. Banning firearms and banning peasants from having weapons only happened in Japan during a 200 year period of peace when Samurai more or less became wandering hobos who spent most of their time eating, partying and with prostitutes. Imposing the Tokugawa dynasty rules on a land that actually has monsters and existential threats and is still warring doesn't make sense. It kind of implies that one thinks Japanese are Klingons or something. Actually, scratch that, even Klingons use guns. So worse than parody Klingons.
That being said, they also shouldn't be the answer to everything. It would be fair to say that firearms technology is in its 1300s to 1500s state. It basically requires one to be stationary, dry and has a functionally long reload time. It has worse range and fire rate than a bow. And since one is likely to die whether you stick a wooden shaft or a stone through them, it is really only good for countering heavily armored troops coming at you. Mechanically in the RPG it could be an unattractive option because you have to be stationary and the long reload time-- you might get one good shot off and then you are effectively unarmed, in the CCG it could be a ranged attack only usable for defense without the right terrain card or action in play.
Swords should not be the master weapon that are so superior to every other and everyone is automatically trained in that it seems like a character flaw to use any other weapon. Swords should not be worshipped, it shouldn't be the end of the world when one gets broken unless it was a particularly important artifact past on from generations ago. Mechanically swords should be properly balanced and have their place as an easily carried weapons good for close-quarters fighting. They are the weapon one is going to be able to rely on when they weren't expecting to be ambushed on a city street or in their own quarters. When one is properly prepared for battle, perhaps another weapon is more favorable depending on how one fights and what one wants to accomplish. Opening up more functional weapon options should allow characters to be better distinguished from one another rather than ever having anything but a sword being an odd quirk of the Mantis clan alone.
Similarly, it should not be considered a death sentence for anyone but a samurai to have a sword. Monsters are real in this world and the peasants need to be able to hold them back until the proper military can get there to deal with them. Certainly because steel is so costly and it doesn't have any other purpose so it should be considered outside of a non-samurai's ability to afford one, but if they scavenge one from a battlefield or one is a wealthy merchant or one has been recruited and trained as part of a militia by a samurai, it can be more or less shrugged off. Granted, any samurai can technically kill any peasant they feel like at any time regardless with, at worst, having to pay back their lord for breaking their property, so if some samurai decide they feel threatened or put upon by having a peasant armed, they can kill them. But it shouldn't be considered a necessary part of a samurai's duty to go around and kill peasants who arm themselves as a stop-gap measure against bandits and monsters when a properly trained warrior isn't available.
Dueling shouldn't be the solution to absolutely everything and no one should be feel compelled to accept duel against obviously superior opponents. Basically if one or two families are going to be the masters of dueling, you can't have it be a thing where they can literally force anyone into a fight to the death at any moment to eliminate anyone they don't like due to their superior skills and be considered honorable for it. By all means, dueling should still be considered a sport, and those who boast about being the most skilled should face off with the winners being heavily rewarded with gold, respect and admiration. But not everyone should feel compelled to compete in that arena. A Hida can feel completely justified in saying to a Kakita "I acknowledge you are a superior swordsman, but I am not going to fight you to the death using your rules nor am I or my army that outnumbers you 5 to 1 going to abandon our posts because you are a master swordsman."
Dueling should be a way to gain lots of honor, but by no means is it compelled. Functionally that classical "You can fight them to the death and the winner gains 7 honor or you can decline and you lose 5 honor", it should instead be "You can accept, fight to the death and the winner gains 7 honor. If you decline, the other player gains 5 honor." Perhaps the challenge can only be issued to a card that has equal or greater chi than the challenger or there could be an action that causes an honor loss instead of an honor gain if the challenge is made to a card with less chi than the challenger. In the RPG similarly it is totally fair for a samurai whose pride comes from something other than being the best duelist around to acknowledge someone as a superior duelist with dishonor likely coming from either someone who goes around challenging clearly inferior opponents or accepting a duel that causes them to abandon or forgo their duties in the vain hope of gaining some personal glory.
That being said, by all means dueling could be part of the setting history about how the clans were originally unified. I mean, its got to be better than "we invited all our rivals saying we wanted peace and would share the power, got them all drunk and then killed them all while they were sleeping" which would be accurate.
Bushido is good to have, but not essential and failures of bushido are not the end of one. Some families proclaim themselves to be the best and try their hardest to stick to the principles, others... not so much and everyone knows it and they are not expected to kill themselves over it. It should be treated as an ideal to strive to live up to, not a code one is expected to adhere to in every single action they ever take.And likely every clan is going to emphasize on of the ideals above the others so that if they come into conflict, they will be expected to choose the value their clan champions. Now, that being said, if one very clearly violates the principle and don't find victory as a result, they might find themselves the target of rumor and ridicule and find it very difficult to have their requests filled and find people don't want to associate closely with them.
Basically, we can say "well, the Lion clan acts honorable all the time so it would be surprising if they did something that wasn't within the code and as a result people prioritize them and give them discounts, favors and cooperate with them easily. We don't expect a whole lot of honor from the Spider clan and so people tend to disassociate with them, jack up their prices, don't do favors for them and aren't very cooperative unless forced by threats of violence or extortion."
Seppuku also has to be considerably more rare. It cannot be the solution to absolutely everything as it has sometimes been treated. Realistically, seppuku happened only under one of three circumstances... either (1) someone had lost a battle and killing themselves was likely a better fate than what the enemy would do to them if captured, (2) Someone was forced to carry out a duty that violated their conscience and so they did the duty and then killed themselves in protest, or (3) Someone was going to be executed, particularly for political machinations that were done to avoid future conflict and they were allowed to kill themselves and be buried with honor rather than the worse fate they would befall if executed as an enemy of the state.
Maybe because of the very real nature of spiritual things in Rokugan it can remain a 'I screwed up so monumentally badly that there is no undoing or coming back from this and it is basically the only way my soul isn't going to be dragged to Jigoku kicking and screaming'. But outside of that, it just doesn't happen-- and it doesn't happen lightly as it should be considered better to live with one's failures and seek to redeem themselves than take the comparatively easy way out. Seppuku erases your mistakes, but also erases your heroism setting you at a net neutral state and people will basically act as though you never did anything of note while working to redeem oneself means one's glorious and honorable actions will be remembered as outweighing their failures.
True shugenja families shouldn't really be a thing. Which is to say that someone born from a shugenja isn't necessarily going to have the same spiritual connection and shugenja can be born to any family-- even to peasants! Each clan would have its own school for training shugenja in their style and those with the natural talent are more often than not adopted or married into that family. For instance, only a small number of the Kuni were born to Kuni parents, others were born to the Hida, Hiruma, Kaiu or the ashigaru or peasants that serve them and then adopted as Kuni. Of course, shugenja born to peasants are targets for the taint, particularly in Crab lands, so the Kuni try to get any child who may have the soul of a shugenja as fast as possible lest they find the child tainted beyond cleansing and have no choice but to execute the child.
These sorts of ideas, trying to bring the game closer to how a real life society could and would function would allow more and better stories to be told and allow it to be a better setting for telling stories of human drama within and a world where clans of varying degrees of honor can all logically exist without killing themselves en masse.
A mechanical idea for the Card Game would be fixing enlightenment victory. The barrier to enlightenment victory is very clear and can be solved fairly simply-- you don't have to draw the rings. The rings are considered in all players' hands at all times. In terms of set up, they would be placed behind your stronghold. Once you meet the requirements, they will be considered activated. They would have to have a less dramatic effect than previous editions upon activation, but enough of an edge that most players will want to activate one or two and maybe it is a bit more difficult to activate them without shortcuts, but you can activate them at any time. Once they are all activated at the start of your turn, you win via enlightenment victory.
As for the story, I would go back to the death of the last Hantei. Basically the emperor's son and wife were ambushed and are assumed dead. Over the next five years, the emperor himself seemed to have gone mad and the once united land has been fractured and small border disputes began. And at last the madness finally took hold of the emperor and he killed himself. Thus the throne has been left empty. Since a civil war happened centuries ago where a younger Hantei killed his older brother and took the throne, the Hantei have had a policy that all other children of the Hantei must renounce their name and claim to the throne. Thus even though there is a fairly decent sized "Clan of Hantei" consisting mainly of Seppun and Otomo with Miya and the Brotherhood being their primary servant families, none of them has any more right to claim the throne than anyone else-- which doesn't mean they won't try.
So the first story arc of the renewed game would be a race to see who can secure the capital and take the throne. There would be 10 factions with 4 initially revealed families each (there might be more families) and each family would generally have a distinct theme to it. To get it down to this number it is necessary to eject some of the families. Maybe someone else can think of a way to expand each clan to 5 families, probably by breaking up some of the families that have too wide of a theme into two distinct families (Doji, Bayushi and any other family who in the 4th edition book had two schools with the same name) or absorbing some of the minor clans. But perhaps it is best to say any 5th family would be introduced in expansions and simply leave how many families each clan has in total an unanswered question.
Crab
Since the dawn of the empire, the Crab have served on its far border with the Shadowlands, a land of darkness at the center of which is a pit to Jigoku itself. All other clans have served with them along the wall, but they are its chief protectors. For what they have done and what they have sacrificed, none can disagree that the Crab Clan is a true leader and uniter of the empire. If they can find victory, they can finally lead the empire in a war on the Shadowlands to finally put an end to its great threat.
Families
-
Hida (force & follower), Hiruma (terrain control and movement), Kaiu (fortifications, item producing and firearms), Kuni (anti-taint/anti-creature/anti-ninja and magic)
General Play:
Military victory focus. Strongest against military decks, weakest against dishonor.
Crane
The Crane are the beautiful and refined artists of the empire. They are the richest of the clans, they produce the finest crafts, they train the finest swordsman, and they rule over the courts with their beauty and purity and body and spirit. As they already control the courts like no other, they can easily shift the empire to a new era of peace once the formality of taking the throne is finished. They alone are pure and refined enough to lead the empire into a new glorious era.
Families
- Asahina (honor production and magic), Daodoji (terrain control and defense), Doji (court actions), Kakita (honor production)
General Play:
Honor victory focus. Strong against dishonor, weakest against enlightenment.
Dragon
Spending most of their time hidden away deep within the mountains, the mysterious Dragon Clan have a deeper understanding of the world than the petty disputes that other clans have. They can foresee the future and know the path the empire must take in order to be successful. Only they have the enlightenment to lead the empire in the new era.
Families
- Kitsuki (anti-dishonor/anti-courtier), Mirumoto (honor gain), Tamori (terrain and magic), Togashi (ring play and use)
General Play:
Any victory condition possible, enlightenment ideal. No particular weakness a long as you draw the right meta.
Kirin/Unicorn
They protect the empire's northwestern border from the barbarians of the desert that live beyond it. They have the finest, strongest, swiftest horses in all the empire. Many of them are descended from those barbarians from years of mixing it up with them. They know to keep the empire safe, they must expand it but the Hantei never gave them the power to lead the clans on such a quest. Once they take the throne they will be able to lead the empire on a campaign to expand beyond the horizons. (Thematically, the Moto will continue to often have Mongolian names.)
Families
- Horiuchi (Movement and magic), Ide (court actions), Moto (cavalry and berserking which may cause taint), Shinjo (cavalry and honor) (Note: Shinjo can take on the matriarchal concept of the Utaku and incorporate that as a wider part of the clan's theme)
General Play:
Military victory focus. Strongest against honor and enlightenment, weakest against military.
Lion
The Lion Clan controls the second most powerful army in the empire next to the Crab, yet are also masters of tactics. Their honorable conduct puts them in everyone's good graces. They are already the effective military leaders of Rokugan, thus its true ruler already.They can easily take the throne by force and once that is done, none will dispute their rightful rule.
Families
- Akodo (tactician), Ikoma (court actions), Kitsu (honor/dishonor and magic), Matsu (berserking which may cause taint)
General Play:
Military/Honor victory focus. Strongest against honor and enlightenment, weakest against military.
Mantis
The Mantis clan is the only clan not descended from one of the original kami that fell to Rokugan. Instead they originate from an island off the coast of Rokugan, and many are descended from the people from the seas beyond it. As the only family that has diplomatic ties to foreign lands, they are the only ones who know about the true threats and opportunities that the empire has stubbornly ignored. By taking the throne, they can finally open up the empire and secure its future. (Thematically, they might get a lot of Chinese and Korean personal names.)
Families
- Moshi (ranged attacks and magic), Tsuruichi (ranged attacks), Watanabe (gold production and court actions), Yoritomo (naval and movement)
General Play:
Military victory focus. Strongest against military, weakest against dishonor.
Owl
The Owl have ruled over Rokugan for over 1,000 years. Despite the recent bad luck that has made them look bad, they alone know what it actually takes to rule. Though they are scattered across the empire, they must work quickly to put their house in order before the other clans prematurely circling them like vultures do too much damage.
Families
- Otomo (dishonor and court actions), Miya (terrain control and movement), Seppun (force enhanced on defense), Brotherhood of Shinsei (ring play and use)
General Play:
Enlightenment/Dishonor victory focus. Strongest against military, weakest against enlightenment.
Phoenix
The masters of magic, healers and spiritual leaders of Rokugan, the Phoenix clan's mastery of the arcane arts demonstrates a deep understanding of the universe. They have earned many favors by putting their healing powers to use for other clans. However, the boundaries between clans have prevented the shugenja from working together properly. By taking the throne they can finally dissolve the artificial barriers between clans and have knowledge shared openly throughout the empire.
Families:
Agasha (ranged attacks and magic), Asako (court actions), Isawa (ring play and use and magic), Shiba (anti-card elimination)
General:
Enlightenment/Honor victory focus. Strongest against Military, weakest against Honor.
Scorpion
The poorest of the clans, the Scorpion have always done what they needed to survive. Masters of stealth, deception and seduction, they rule the dark corners of the court and always have a myriad of ways of eliminating their enemies. The Scorpion clan tends to be looked down upon by the other clans, but they are far too feared to be confronted often. The throne being empty is a chance to finally change their fates for the better. Moreover, only they have what it takes to not only seize the throne, but to hang onto it as well.
Families:
Bayushi (dishonor and court actions), Shosuro (Card elimination and ninja), Soshi (dishonor and magic), Yogo (Card elimination and magic)
General:
Dishonor victory focus. Strongest against honor, weakest against enlightenment.
Spider
Not an official clan, but rather a large collection of ronin and 'lost' samurai that has formed itself into an organized collective. They are mistrusted by all other clans for all the horrors they are believed to engage in. A surprisingly large amount of the rumors are in fact true. The Spider Clan claims to have located and rescued the true heir to the throne and intends to put him upon it. But no one is certain whether or not the boy is indeed the emperor's son. Still, they may have the most righteous claim to the throne, as much as no one would be happy with an emperor who has been influenced by the Spider.
Families:
Chuda (card elimination and magic), Daigotsu (berserk, may cause taint), Goji (Card elimination and ninja), Order of the Spider (ring play and use)
General: Military/enlightenment victory focus. Strongest against enlightenment, weakest against dishonor.
Ronin/Minor Clans
A lot of players have a lot of fun with these. Ideally there should be enough unaligned cards and they should be useful to various deck types, not just military, to the degree they will actually find play. At least if your clan doesn't have the cards necessary to achieve a victory condition or enough meta against a weakness natively, it would be better to use an unaligned card to shore up those weaknesses rather than take another clan's card. There would be an unspecified number of minor clans. I would rename any of the ones that were lazily named after their icon animal. Kitsune, Kaeru, Tonbo, Koomori, Usagi, etc. all need new names. Really it was uncreative, came off as way too unlikely and got way out of control.