Breen is more like a brown nosing puppet than a Evil Genius.
But you right I wouldn't mind the "evil" genius part too much, I much more picture myself sending an army through an inter-dimensional gate to enslave entire universes, rather than selling everyone out so I can go and run some lousy city.
If Xrain was truly an evil genius, he wouldn't be like those kinds in the superman series. He'd be the real life, scary as f**k kind. He would probably develop a deadlier version RVX, make an example of a city, then hold the world in terror, doing his every will. Or if he was truely evil, he would develop a gas the casues all muscles to lock, stops endorphines, and makes every nerve to sense intense pain, then they die about 15 minutes later. I'm glad Xrain is not an evil genius.