Well, I'm now going to join the list of people who've complimented you.
I think that it's wonderful that there's someone out there who'll tell people that they have to improve, without being afraid of their reactions. I've looked over so many pieces of "art" and thought "I want to throw this in the trash!!", but I don't say anything. Seeing someone like you is a huge relief, in a way.
I actually had a gfight with my oyfriend once...he kept insisting that my art was good, but I didn't want to hear it. I've always heard "It's so good!" and it's tiring. I asked him "Are you being HONEST-honest, or BOYFRIEND-honest?" Those who're close to you can't bring themselves to critique, for fear of hurting you or getting you angry with them.
Being told you need to improve is something you want to know, even if you don't want to HEAR it. And people need to be told.
I'm not God of Art, but I know when I see bad art (I see it every time I put my pencil to the paper). I can't find a word to describe how grateful I am to people like you who'll tell people what they need to know.
Keep spreading your wisdom.