Thanks for the input all!
I really appreciate your thoughts and analysis.
I do see a problem with the arm length thanks for pointing that out, I'll work on that and slightly adjust the shoulder structure too.
She's actually received a couple shrinks to her shoulders already but perhaps another pixel can be shaved.
She's definitely supposed to be athletic and not a traditionally figured woman, but more of a fighters build, if you look at this lineup of MMA women, you can see they have pretty broad shoulders:

They idea for the face is also to keep it clean (no makeup) and natural, while trying to preserve that feminine smoothness but also not go too far into "cartoon lamb" face territory. I definitely thought about the perspective of her face, but just like in the photo lachrymose posted, you can see that a fighting stance when viewed from the side typically has a 90 degree turn. That's why I put her face more in a 3/4 view for the charge up stance.
BTW jahasaja, she's supposed to be gritting her teeth in that facial expression, it's been hard for me to nail this down with just a pixel or two, I'll see if I can refine it some more to be more clear.
This is the reference I'm using for the 3rd stance (transitional stance) -
