Hey, I'm back (again) with my Sonya and a new animation. Hope you like it!
http://jhonatasbatalha.deviantart.com/art/Jumping-489653980
That's just amazing, man.
The realism you achieve is incredible.
I do agree however that there's something strange with her head.
Her chin is too far from her neck, meaning her whole face should be closer to the vertical axis of the head, making the head seem smaller horizontally.
That looks amazing too.
You were right about the hair.
What doesn't look right though is the way the hand stops at the back.
Try enacting the thing.
You won't have a smooth stop at the end and the arm is moving further behind than it probably should.
The arm and hand should violently reach their limit of motion in the frame below, stop there for a second, and from there the whole arm should go down sideways into its idle position.
The limit is very close to this frame, which is where the sprites stop in the original game.
Also, at that point I'd try to make the elbow and wrist have more of an inward arch.
Also, in this animation it becomes much more apparent how black and sleek you made his back, almost as if he had tar smeared on or something. :/
Can you perhaps try making the texture more transparent, so that the base color is still his skin tone, but has those black spots?
Just a test to see how it goes.