Going back through a few items, some related to the Big Ten rights negotiations upcoming in the next year. The rights that are housed in BTN aren't up for negotiation, but the rest will be and there is the belief that FOX will be active in acquiring a portion of the rights they currently don't have.
Besides the college football that FOX Sports 1 already carries, there is also MLB, NASCAR and UFC that the network carries on Saturdays, so it is rare for the network to have just college football shown on a particular Saturday. So the focus comes to FOX Sports 2, which doesn't have the distribution number that FS1 has. Typically FS2 is on a different tier from FS1 or it might not be carried at all. FS2 was subscribed to in around 33-37 million homes coming into the year compared to around 85-90 million for FS1, so there is a big gap.
For the Big 12, Pac-12 & C-USA content that FOX has rights to, there are differences that FOX can exploit. These come from press releases, not actual contracts, so we don't know the exact language being specified. Many of these press releases listed FX or FSN as well, but FS1 is more or less a direct replacement for F/X when it comes to FOX's national sports content.
It is probably easier to exploit the Big 12's and C-USA's contract provisions. Both conferences place games on FSN and FOX College Sports. The Big 12 has a very low minimum number of just six games on a national cable outlet, so their agreement may have been built to be flexible with a secondary outlet or FSN in mind. C-USA's agreement may be built to be flexible. I'm less certain about the Pac-12.
But the ability to schedule a game for a particular outlet may require FOX to guarantee a level of distribution for that channel. Could be why FOX still puts a decent number of Big 12 & C-USA football on FSN instead of FS2.
So I ask you - if you were a conference commissioner negotiating rights for a conference and FOX wanted to move games to a secondary outlet like FS2, what would be the minimum number of subscribing homes you could accept nationally? Does it have to be 1-for-1 with FOX Sports 1? Can it be closer to ESPNU (~75 million homes) or lower like CBSSN (~60 million) or BTN (~59 million)?
And this isn't saying the network can't grow from there. Doesn't have to be a big time game either, but what is that minimum that you would accept to schedule a game over there?