He didn't start as Orc supremacy. He wanted everyone to subdue to his methods, the other leaders didn't agree and said fuck him, then he decided to shove them aside, which was basicly his downfall, his methods. Also don't give me that bullshit about ruined character, get outa here with that. He has been build on warmongering and conquest. His downfall was deliberate and obvious the first momment that Vol'Jin spat on his face during that starting Area vision.
Hes still a character that made things happen atleast, which is refreshing because half the racial leaders are freaking boring. Though I like Vol'jin and Lor'themar.