Some of my shtuff!!! O_o

I think you did a pretty nice job with most of these. My favorite is this one-

because I like the effects directly to the left of the render.

What I think you could use the most improvement on is text. I'm no good at it, so I can't give very helpful advice. Your text isn't even terrible, it's just that I think the sigs would look better without it in most of your examples. >_<

 

^ I disagree, I think you could use text for any number of things (like perhaps setting the tone of the piece), as long as you do it effectively. But too often, I think it tends to drag the signature or avatar down, rather than improve it.