Thread:LostGod2000/@comment-10876881-20150304191648/@comment-1762629-20150304230944

Any "further games" are purely speculative at the moment- Nintendo hasn't announced anything at the moment, and we only have what we have. And how King Boo is represented in Dark Moon has him void of redeeming qualities. The only generous side he's ever shown was towards his Boos, and considering he treats them as disposable pawns in the second game, that's gone. Besides, I'm not sure if go-karting is a true redeeming quality. He's only done it a handful of times,  none of them since the release of Dark Moon, it's questionable whether he's doing it out for fun or not, and in other games he's little more than a boss to be fought.

Luigi's Mansion is the game that actually gave him a character, something to be measured by, where as the other games have nothing. I feel it's that we should be measuring. TV Tropes has already listed him and other mitigating points you present have likely already been debunked.

From the sole (sub)series he has a character in, he's proven to be definitively beyond redemption.