I'm really inexperienced as well, so I may be alone on this, but I feel like you're trying to hard to get the animation by just changing the shape. You can achieve these subtle motions and movements by minimizing the change is shape, and instead shift pixels around. Also, maybe start with trying to animate a much smaller piece? I have found myself learning more about animation and how to achieve a sense of life while moving as few pixels as possible because I am working on really small pieces. 24x24 and 32x32 tops. But like I said, I am very new to this as well.