I think it's kind of fun to be on the "dark side".
But the way you name it doesn't really matter. How about "quasar" and "black hole"? Still makes the latter sound negative though, I guess. The point is that both of them are very powerful when they reach their full potential -- one spits energy out, the other draws it in and swallows up anything that stands in its path.
Even quasars and black holes work together though. Wikipedia says that "quasars are believed to be powered by accretion of material into supermassive black holes in the nuclei of distant galaxies..." Which from my understanding means that the black hole is ultimately what makes a quasar possible. So I wouldn't get hung up on the choice of words. Just pick what feels natural to you. I like the idea of being powerful, unstoppable, and achieving a lot.