In principle (assuming Ga/U-M win as expected and remain 1-2), I prefer sticking to 1-2-3-4 rank regardless of conference, IF that's how committee assesses the pecking order. That's a big "if." If the assumption is Ohio State should jump TCU because it has a better loss between the two, go for it.
As for what's "preferred" for the semi/final matchups, I'm sure they could massage it into whatever is deemed most attractive and most likely outcome.
I will say, if I'm a U-M fan, and had to rematch Ohio State in the semifinal so soon after beating OSU on the road AND getting to the B10 title game AND winning conference title, I'd be a bit pissy.
If they're 2 & 4 and each advances to national title game, that might suck to have to prove it again, but in that case Ohio State would've upset Georgia and "earned" its way to a rematch.