When people talk about making martials "better" there's scant suggestions on how to do it other than to make them into some variation of a comic book superhero with no details. I don't want my fighter to suddenly be able to shoot laser beams out of their eyes, so what else do we have?
Plenty of ways to do it without going near the superhero route.
For ex. Allow fighters with superiority dice to add them to more things.
Say the fighter wants to jump farther, he can add a superiority die. Doing this won't go near superhero levels, with the added die he might actually approach what a trained athlete can do (in the RW).