Haven't we seen this lil guy before/
Anyways, thing I'm noticing right off the bat is that one of the legs shoots up into him straight but the other seems to bend at the knee some, giving him an off-balance appearance. The arms seem to be notably overlaid atop the body, since they don't have a fixed joint area or "tracks" along which they could be meant to slide. Face has the same problem, instead of bounding the whole screen I'd make it slightly larger and bounce the face instead.