Tone down the lighting above the render, he's white enough. Also, make the text stand out more so it's more legible and position it better, perhaps on the left over his shoulder or on the bottom right side under the render.
I know how that cafe likes their borders, and I actually do think that sigs need some sort of border on this light/washed out forum skin, so try to be more creative with it then a simple 1 pixel black border. From my past experiences I have found that thicker borders tend to look better, so try to thicken it to around 3 pixels or so. White may also look better. And for certain sigs, a grunge-ish border can complement the sig quite well. Try using brushes or stocks to achieve such a look. Just play around and be creative with it.
Wait... what? SPC's back?