I disagree, the Legion is bad in my opinion. They torture and kill everyone they don't like, laugh at how nobody rebels against them, and all the woman they capture are used as slaves (most likely in more than one way if you get what I mean). Besides, what did Nipton do wrong? So they weren't the nicest people, they were neutral, they helped anyone willing to pay regardless of faction, and for that they were slaughtered? How is that fair. Do you think refusing to help anyone would have helped much? No, because the one they refused to help would just attack them. Yet if they chose to help one faction, the others would attack them. They just got stuck in a bad position and the Legion just needed to kill a bunch of people to prove a point to the NCR.