[Autumn]

When you use Mixed Martial Arts its still a bare fist weapon, it just costs a skill slot instead of a weapon slot, you also gain the benefits of being able to use many good glove items. (As well as 2hand)

On top of that, if you just wanted to use a fist weapon, you give up 2handed but you get a better scaling fist weapon overall, which improves your damage for martial artist.

I don't see why you'd want to use bare fists regularly when MMA offers better payout, what is the setup you're trying it on Shujin?