So I know there are many threads like this, but I will be limiting this one to strictly Canon material that we have seen in Movies, Cartoons, Novels, Video Games and Comics throughout the Mouse's takeover of the Star Wars franchise. Luckily we have finally gotten some more material from Rogue One in the form of Wave 14 (AKA Wave 13 if you really think about it) but there is still more we could get. So heres my list of material that I think and you guys can judge me or curse me all you want, haha.
Starting with movies, we will again start with Rogue One:
I love the addition of Saw and his Partisans, but we still need the Heroic General Antoc Merrick and Blue Squadron which consisted of three different ships in the X-Wing, U-Wing and Y-Wing. We could also pull 2 new Rebel Epic ships from Rogue one in the form the Hammerhead Corvette which would be a good missile platform for the Rebel epic scene and the Braha'tok Gunship would be a great Anti-Fighter ship which the Rebels are sorely lacking. Unfortunately I can't think of any Imperial assets that could be utilized unless we want to do another Tie Fighter Expansion that brings in the Scarif, Eadu, and Jedha patrols or Krennics shuttle.
Moving on to LTJ, again all I can think of is the RZ-2 A-Wing from the beginning of the movie and bringing in Tallie Lintra and whoever else they can come up with, and maybe the shuttle that Finn and Rose stole when escaping the First Order to get to Crait.
So that is all I have for movies unless people want me to go into the Prequels which I doubt, haha.
Next up is Rebels which still has a wealth of material and in my mind now has the most material to give us since we got more Rogue One material. Main thing I want is Phoenix squadron A-wings and X-wings in the different paint schemes for both fighters. A new YT-2400 with the Iron Squadron crew as pilots and crew cards and the Sentinel Class shuttle for the Empire and for Scum with Hondo and his crew as pilots. We could also do new Y-wing pilots in the form of Sabine, Zeb, and Ezra, along with the other members of gold squadron shown when the Ghost crew is saving Mon Mothma, and throw in the Defender pilot who's name escapes me right now....
Moving onto Novels, my personal favorite right now is Tarkin which is based on the early Tarkins life and recent management of Death Star materials. The thing I personally want the most from this is the Carrion Spike which was Tarkin's Personal Corvette before he took command of the Sovereign, and this could bring in some interesting new mechanics because this ship could cloak and could scramble other ships sensors making it harder to hit. Another thing I would like to see is the addition of V-wing into the Imperial faction and bringing Tarkin in as a pilot. It could also bring in some new Z-95 and Y-Wing pilots into the Rebel faction if you consider the Antagonists in this movie to be true rebels.
Next one up is Lost Stars, from this we have another wealth of pilots for both the Rebels and Imperials. First and foremost is Ciena Ree, who is a pilot that I have grown to love within this universe and would be a great edition to the Imperial Interceptor ranks along with Nash Windrider who I believe flew both a TIE fighter and Interceptor but would be a nice fit in either one of them. One we already have is Thane Kyrell, but we could use him in an X-wing along with the rest of Corona Squadron.
For video games, there is really only two things we need in the form of Inferno Squadron for the Empire, then Danger Squadron for the Rebellion with appropriate Iden and Del pilots.
For comics there are a bunch of things, one would be Evaan Verlaine as a Y-Wing pilot from the Leia comic, Lulo Lampar as an A-Wing Pilot from the Poe Dameron comic and there are honestly too many more to list from the comics but if anyone else knows of any feel free to add them.
So this is my start and if we talk about who and why we want them in the game and ways the developers could add them maybe... juuusssttt maybe they will add them like they did the Gunboat after such a long thread.