I think you do a great job building believable monster-like characters, but I feel that your figures are suffering. I'd recommend picking up Drawing the Human Head By Burne Hogarth and maybe even his other book Dynamic Figure Drawing. Hogarth uses a really exaggerated, almost comic-book style, but he does this to more clearly illustrate his points. Take what he says from these books and relax some of the rules so it tailors to your style.
I think you have a very fun and recognizable style, stick with it!