with the brushes, most of the time what I do, is I start with just making the background, when there is nothing else in the sig yet, and I brush with black and a very little bit of white ( on different layers), then, i make a new layer, make it totaly the color I want say "blue", and I either tone down the opacity enough to where the background looks good, or I set it on overlay. it makes the bg look better imo.

but ya, your getting better, looks good man.