I think that he, like most characters, would believe that he was the hero of his own story. Whether others view his actions and motivations as good, evil, or somewhere in-between depends entirely on their perspective.
Except it is never explained what his actions were. We cannot view "his actions" as anything but how our character interprets them, which is apparently bad but there is absolutely no explanation given for why they are bad.
"Betrayer of Horadrim" yet there isn't a single hint in the entire game as to how exactly he betrayed the Horadrim. He never killed any Horadrim, as far as I know, he simply had different views than them. If that makes him a Betrayer
then it raises the question of how well these labels are applied.
It doesn't depend on the perspective, either. The perspective is given by the story telling. If some people think that your character saying "You must be stopped!" makes the character evil then they're simply believing whatever they initially think they should believe regardless of the facts that would back up that belief.
But then someone like myself thinks, "Well, he actually hasn't done anything evil that I can see" is not viewing it in a different perspective, its just looking at the facts that would support my belief. I'm not saying he's good or bad, but from what is presented to us throughout the game there is no way to tell whether he is good or bad, but then he is dismissed as an "evil" character (which is just bad story telling).
It should be evident that the character is evil, we shouldn't have to simply assume he is because he has a raspy voice and laughs a lot... that just supports poorly constructed prejudices. Why isn't the Demon Hunter evil? He certainly sounds evil. From what we know, he's just as evil as Zoltun Kulle.
Bad story telling is bad story telling. It has nothing to do with "perspective".