I think the up/down motion of the torso is not subtle enough. In fact, you could probably do without it. There are also some frames where the cloth is in the same position as the previous frame, making it seem sort of choppy. If you're going to make an entirely new frame to move one piece of his costume, you might as well change the other parts slightly too, to make it look smooth.
Anyway, it looks really nice, and with a little polish it could be a very cool work.