On one hand, he killed loads and loads of slavers, and helped to bring down their extremely brutal empire by aiding a slave rebellion. On the other hand, he also killed a bunch of people who probably didn't need to be, to the point that the mer describe as the leader of a Elven Pogrom, and he also killed a bunch of Khajiit who weren't even doing anything because he mistook them for elves.
He was also a gay insane cyborg from the future with a Mega-Man style arm cannon, and I'm not sure if his homocidal tendencies inspired from his Shezzar-Akatosh Duality Madness make him 100% responsible for his own actions.
Even the elevator pitch for a lot of these concepts is cool as hell. Knights of the Nine is "hey what if The Terminator (1984) happened basically beat-for-beat in the elder scrolls history except skynet was fighting racist elves instead of humans, and then you had to go finish the T-800's unfinished business? also what if we casually threw in the fact that elves used to have feathers"