Umm, "nobody is perfect so all of them must die" is pretty close to pure evil.
That exact attitude is what has motivated many real world atrocities; someone has looked at the world as it is, found it wanting, and self-appointed as judge, jury and executioner - always with the purest of intentions.
Nobody is perfect? These factions aren't Justin Bieber fans or love pineapple on pizza kind of evil. It doesn't matter if you ignore all of them or not, they'll all want to attack you once you reach the end unless you've taken their side, it just depends on certain calculations which gets to do the honor. If the game allowed, they would all line up and attack you if they could. So