The general gesture of this is great, I think you just need to focus on smoothing out the animation. I would definitely up the frame count. And just give the shoulders/chest another pass, the movement there is a lot choppier than elsewhere.
As far as the drawing itself goes I'd only really suggest that the legs are a little short and the colour range is a bit off, none of the different colour areas really seem to match each other in terms of brightness or number of shades.