I just think it doesn't look right. I can't say exactly why, but something in my head is telling me it's not natural looking. Maybe it's the stiffness in all the other body parts, I don't know. She moves them up too slow or something. Same thing when she lands on her foot after jumping the air, her head is perfectly straight and never moves. Wouldn't gravity force her head to at least bob a little on impact? We're being picky, but maybe some of this will help you perfect the motion?