Team Flare never really left an impression on me...I dunno, maybe it's because it felt like X and Y shoved 90% of the plot into such a small part of the game.

But yeah, egotistical villains can be a lot of fun. Same with overly hammy, theatrical or flamboyant villains. I mean, I don't really have anything against other types of villains, I just find those more entertaining.