I think you're kidding yourself when saying "the empire aren't the bad guys". Of course from a Sith's point of view the Jedi is the enemy that hast to be purged and from the sight of the Jedi its the other way round. But as a neutral viewer watching the movies, reading the books or playing the games you have to admit that the most horrible things in the Star Wars Universe were done on behalve of the Sith Empire (Alderaan, Taris, Order 66 to name a few). Bad (at least from my point of view) is is to gain an advantage even if others have to suffer for it ... and this is like the motto of the Sith.
That doesn't mean that every member of the Sith Empire is evil. As your roleplaying goes you can be a Sith being mister goody nicey guy helping everybody and making the universe a better place to live. Or you play an a**h*** of a Jedi slicing everything that moves and do other unspeakable things.
I'm playing empire btw
€ Damn my browser is slow -.-