1. A CCG after a round-robin season is an abomination. It's a guaranteed rematch (unlike what teams in the other four P5 conferences necessarily face), which means it devalues the regular-season game. And a rematch is a bummer for the winner of the first game. I hated seeing OU lose to Texas in October, but it would have been even worse to have won that one--the traditional rivalry game--only to lose to Texas in the CCG. I imagine Texas fans felt that way. I'm sure Nebraska fans felt that way back in '78 when Nebraska beat OU in Lincoln only to receive a rematch in the Orange Bowl as their reward. IIRC, with 2 weeks to go last November, OU, UT, WVU, and ISU were still in the running for the CCG. I think I remember that ISU-WVU was a possibility. And if WVU hadn't tanked, the 'Eers could have been in the CCG vs. either OU or UT. That would have been better than vs. ISU as a national attraction, but not nearly as good as OU-UT. As a national game, OU-Texas moves the needle like no other match-up in the Big 12.
2, 3. I don't have facts at hand to argue the revenue points, but I would hope that if the B1G came calling, or more likely hinting, OU at least would listen and respond with a request for membership. And not primarily for the football revenue.
It wouldn't kill me if OU and UT ended up in different conferences as long as they agreed to keep the annual game in Dallas. But I think the B1G would be more likely to hint non-AAU-member OU's way if the potential for a package deal were there.
It also wouldn't kill me if the Big 12 continued to bump along. But I think WVU is a point of instability. I'm sure when they joined the Big 12, they anticipated--or at least hoped for--another team or two in the Eastern time zone being added. Now that that seems to have been nothing but a pipe dream, if I were WVU, I'd be trying to find another home. Granted, their options seem to be nil, but that doesn't mean that they aren't dreaming of going elsewhere.