Looking good seems to be a a Sonic Station, headphones at the ready.
About that central decal, it looks rather cool, though perhaps you could make the black blacker for a fully transparent effect.
I use http://www.xnview.com/ to do that kind of thing it's free and simple to use. Image > Adjust > Levels, then adjust the black point until all the blacks go completely black and your set for full black transparancy.
exactly what do you want done to it? do you mean the blurry edges? I can crop it for you if you want and clean up those edges...