Feather the enterprise.
For the backround i like to make stars by doing.
Edit: start with black backround.
1. Add noise :AddNoise:
Intensity-40
Saturation-0
2. Brightness/Contrast
Brightness-80
Contrast-90
Doing this makes the stars have more distance apart from each other meaning some are brighter than others.
Or maybe this for the background:
http://paintdotnet.forumer.com/viewtopic.php?f=15&t=21260
Otherwise it looks great!