My Super Kool Art (Yes that's kool with a K!)

Man, those are pretty cool. I like those! Here is a torterra!

Any advice on how to improve?

Well, what program do you use?

I'd say lay off using the effects like I did when I first started with photoshop. Download custom brushes with cool designs to use on your signatures, and use stuff off that effects list as little as possible. I'd use blending options.

EDIT: Also use better stocks and renders that have good quality and are cut out well.