Wow, I have missed the magic of finding great music in weird flash videos.
This sounds like lemon demon, the crazy coot.
Over all, this was quite funny, and I would say in terms of the art, it's ok to have faces be that simple, because you kept their face's shape and over all tone (emotion and muscular) consistent.
I would recommend working on the limbs, as the one's you have hang a little oddly.
I personally know I got alot out of practicing redrawing some of leonardo da vinchin's muscle notes.
I obviously don't have his talent, but I learned a little bit from his eye on the nature of muscles and how they balance out.
Keep in mind some of his stuff is speculative, and people are naturally physically unbalanced, but understanding why the the physically moves in certain way helped me alot in life and in sketching.
This did just make in general though.
Thanks for sharing.