Not sure about this whole weary vs. tired debate. Not going to get involved

... in order to reach his goal...
Exactly. All things to reach his goal. What goal though? We're not sure.
One question? If Kellhus didn't care, why wouldn't he just say the he'll with everyone else's soul and join the Consult?
Well, if his goal is to kill the Consult, its probably that he determined that TGO was the best way to do that. Joining them may not have been an option. Too many unknowns that route regardless.
He wouldn't need an Ordeal, he could reduce Earwa population on his own with his army and schoolmen.
I'll give this one a maybe. The scholastic wars ended devastatingly for the schools. There are a lot of chorae around, doing that himself would be tough, even with one or several schools. Easier to send the entire population of men into the wilderness and have them killed by endless sranc.
He's weary because he has a job to do for humanity,
He's got a job to do for sure. For humanity? We'll see.
that no matter how awful it seems now, no matter how many dead fall in his wake, he will accomplish a world without the Consult and the certainty of damnation. He's weary!
A world without the Consult seems like a goal of his. Though, imo, its just as likely to be for his own gains than it is for some altruistic reasoning like "killing damnation"
All Kellhus needs is to put his feet up for a while with a nice cup of tea. 
"Tea" = Chanv laced anpoi.