Four of my signatures

http://img12.imageshack.us/img12/2830/championn.png

http://img339.imageshack.us/img339/9671/strange.png

http://img526.imageshack.us/img526/6509/cloudsig.png

http://img504.imageshack.us/img504/4838/energyl.png

Overall, the text and placement is a little off. Only in the first one do I feel does it work. The "strange" in your Dr. Strange sig is really off, IMO, but the sig itself is really well done. You kinda went a little overboard on the Cloud one. It's hard working with two focal points, so a bit of editing might want to be considered?

The first one is a bit too pixely for my tastes near the render, while the last one is fairly... bland.