If you think about it… aren’t you slightly affected when a character taunts you?
I think a taunt should cause stun propotionate to the length of the taunt. It’d also stop people from taunting just because you taunt, and attack instead.
I think that if you can complete a full taunt, it should add some stun to your opponent.
Ryu’s “Get serious!” taunt. 1.5ish seconds. 150 stun.
Makoto’s “Wow! You better try harder!” (she sits down) taunt. about 5 seconds. 500 stun.
You can’t stun an already stunned character, so the taunts after stun would be empty… but for show.
At any rate, I think it’d be a neat addition, and motivation to taunt.