Not trying to be rude, and you're certainly not bad, but there's something about your style that slightly annoys me. I think it's the way most of it looks really sketchy and quickly made. Take your time with your work. Your line art looks almost like you drew it at a low opacity for some reason, you should try doing in just with a solid black brush, I think it'd look less messy that way.
So basically do what other people are saying and refine these son'bitches so they look more solid and well done rather than sloppy and sketchy. Though you do appear to have improved some since the thread started.
Oh, and if you want people to post here more, do some bigger projects. You make a 15 minute sketch of a very simple character like you've been doing, people'll think "Thats neat", but if you do a bigass picture of something really awesome looking with really tiny details, people will have an urge to praise you. I find that on the art forum people often only post if they're really impressed or you're so bad they can't resist calling you on it.