I'd put "Vigilantes" between Mercs and Bandits. Champions above Heroes, and I would move Murder Hobos up above Bandits, as they aren't evil per se, just driven by treasure and XP gathering. Munchkins need to fit in here someplace. Min-Maxers also fall on this spectrum as well. Really evil... uhh... Slaughters? Umm, not finding the word that's PG-13 for this. Players who have their characters kill people just for the sake of killing people.
[Edit] Psychopaths! That's the word!