I have a couple beefs with how armor works. Let's start with the least important: the purpose of armor is not to prevent fatigue in a fight, it's to protect your precious organs from getting stabbed. I'm pretty sure the way it works in RAW is an artifact from early beta. In the first version, Fatigue had a different name ("wounds," I think, much like Genesys), and worked much like Genesys wounds and Hit Points in D&D. That is, they're a combination of superficial wounds and fatigue. Wearing armor protected you from a lot of the little cuts and such, so it made enough sense. Then, they made the (very good, in my opinion) decision to completely separate Wounds and Fatigue. So now, if you don't take a Critical Strike, you haven't really been hit. But as armor is written, it does very little to protect your organs, but it prevents the fatigue of all those katana strikes that you're blocking. Yeah yeah, "It protects your organs because you have to put less effort into defending yourself, so you're not pushed over your Endurance Threshold." Look, I would happily accept that argument if I thought RAW armor helped streamline the game. I don't complain about Armor Class in D&D (much), because even if it's not super realistic, it's simple and gets the job done.
BUT! The way armor works slows the game down. The first is just resolving an individual strike. When my players make their attack rolls, figuring out damage goes: Weapon Damage + Successes - TN - Armor. The Weapon Damage and TN they generally know up front, so it's easier to account for, then I have to pay enough attention to the armor being worn. And then I have to tell them that their strike for 5 damage is actually only for 1 or 2 damage. That sucks.
It also slows down the fight by dragging out the rounds. Our Hida got into a scrap with a Lion bushi, and they were both decently armored. They went back and forth, trading successful strikes, but kept inflicting very little damage because their armor would soak all but one or two of them. It was mind-numbing, and was only saved by the Hida finally rolling a decent crit and getting the Lion to concede.
So, I've been considering changing Armor so that its Resistance adds bonus successes to resist Critical Strikes. The effect on Minions will be pretty negligible (but who cares?), while fights between important folks will go much more quickly (perhaps too quickly? I may need to adjust some weapon damage down by a point or two). But that armor is still going to go a long way to saving your life.
Of course, my big problem is the ripple effect this will have on other parts of the game. Way of the Crab (already pretty strong) is almost the exact same effect, while Striking as Earth and Striking as Water (and also some related Opportunity options) don't make a whole lot of sense.
There are probably a lot of other strands I'd be disturbing by playing with this spider web, so yes, I know it's a potential mess. But I really feel if the designers had considered their "Hit Point" system to be "fatigue, not wounds" from day one, this is how armor would work. And I'm not exaggerating when I say that this one drawn-out fight killed a lot of interest for this game among the players at my table.
Does anyone have ideas of how Way of the Crab, and those elemental kata and Opportunities could work with such a change? Are there any other glaring oversights I'm missing?