Agreed, it is pretty hard to break the game (in home play, not official play) anyway. The GM can control anything they want....a point or two of AC or a few extra HPs or more uses of Ki//Di/Focus isn't going to break the game.....I really don't understand the devs' insistence in such a hard distinction between unarmed strikes and weapon attacks. From my perspective, there is really no good reason not to make unarmed strikes a weapon. It would simplify so many features, and open up a ton of design space and build options.
Sure, I can see plenty of unintended consequences, but pretty much all of them are either hilarious or badass, and none that I can think of would break the game.