I'd say RG is fine. He's good at pretty much every level, and he doesn't have any glaring issues.
Mace, on the other hand, is incredibly underwhelming. He's one of the most powerful Jedi and skilled lightsaber wielders of his time, yet in-game he's got 1 passive force ability (that isn't all that great), plus a couple lightsaber attacks that do impressively small damage. It'd be like if they gave Yoda the abilities of JKG.
However, I'd say there are characters who need reworks more. Mace is meh, but other toons like GG are almost unusable.