Depends on how entertaining they are. Not /co/ but in Nausicaa the manga version the main badguy was the Doric emperor and he was basically evil for the fuck of it.
But he was so fucking fun to watch for the few scenes he had. You wish you loved anything as much as he loved being evil. He was so affable and nonchalant about it all, instead of the dark foreboding badguys you see.
While everyone was serious and shit he was just having a good time, even when he got brought down he was pretty matter of fact about it, end cracked wise.