Your animation style is very strange. It's very rough and primitive looking when going frame-by-frame, but the movement is so fluid like it was done professionally. You really know how to stretch those expressions to the point where it really felt like a classic hand animated cartoon!
And unless you were going for this "child crayon drawing" look, I'd suggest playing around with different brushes to see what would fit these characters, and even play around with drawing nature and basic 3D shapes to get those backgrounds looking less flat.
All and all, you've got amazing talent (and I kind of envy you)! Just keep doing what you're doing and you might be unstoppable.