save it as a .JPEG, not a .GIF, you'll get better quality this way in the future.
I do really like it, the only thing that I see is that it could use more of a focus.
Instead of my eyes spreading all across the sig to see the render, the text, and the lighting source, take them all and make a focal point to your sig.
Making a focal should also help with the flow of your sig.
I like your colors and how they all go together very well.
Bottom line: I like it.