Nice standing frame, but I would add more walking frames. 2-frame walking is extremely limiting, and 3-frame (A-B-A-C) will never look right. You want 4 frames minimum for a good walk cycle, ideally 6 or 8, each distinct from the standing frame.
For the walk frames themselves: you should consider stronger foreshortening and much darker shadows on the distant limbs. Currently there's not much separating the standing frame from the walking ones, light-balance-wise. Also I'm not sure what's going on with the bottom of the forward feet. Is that supposed to be the bottom of the sole? Because that would never be visible from this angle, and the perspective is off on it anyway.