Really hoping that Great's "corruption" isn't cured and that he remains an antagonist. Great is a pretty fantastic villain; I think he's been established pretty well as absolutely untouchable, and it's an interesting story element to hold on to.
I personally hope it is "cured". But that he essentially keeps being who he is now.
Great is an interesting character because he's not a wholesale cookie-cutter villain. He doesn't want to dominate the world (it seems like a pain in the ass). He doesn't really want to work with the administrative elders, other than the fact that he likes their laws. He doesn't really want to work with the revolutionists because they want to change said laws.
He's in an interesting position, and it would be sad for that to tilt too much in one direction or the other.
Him becoming corrupted presumably makes him subservient to the person that corrupted him whenever he and Bear fuses. Otherwise I have no idea why that person would want a completely evil all powerful entity that would likely cut him down on the spot.