First off - ballpoint pens are awsome aren't they? They were my favourite medium for a while; kudos
I really like the flow and energy of your work. You have a great almost angular style.
On that note, I think it would benefit you in a big way if you filled up a page full of lip studies. Even if you do draw in an anime-esque style, it'll defenitely help you learn how to at least insinuate a full pair of mouth flaps without making your art look at gangoru or however you spell it. Y'dig? EH?
If this doesn't make sense, I'm really sorry, I'm kind of .... incoherant by nature.
Keep it up m'friend