There would be less interest in both of these playoffs, IMO. They would both make plenty of money, but they aren't going to make more than a big playoff that gives everyone a theoretical shot. One of the reasons March Madness is so well watched is because everyone at least gets a shot at the same crown and occasionally Cinderella makes a run.
The Big 12 and ACC just want some guaranteed access. Is there a reason the SEC and Big 10 can't accommodate that? They're already making far more money, and the playoffs will be set up in a way that they make the most. This whole idea of a break away is fueled far more by this desire (that's always lurked in college sports) to have an exclusive tree fort that the ugly kids can't play in than it is about long term financial success. Big 12 and ACC fans are going to watch Big 10 and SEC games when they know that those are schools they might play in the post season. If they aren't competing for the same thing, they're going to watch a lot less of it. The whole thing seems predicated on the idea that the left out schools will just become fans of Big 10 and SEC schools, and it completely misunderstands the whole root of collegiate fandom.
I enjoy watching the FCS playoffs when I get a chance, but it's not appointment television because it doesn't really affect my school or who we play. That's what will happen (in each direction) with further splintering. The only way I see a splintering possibly making more money is if it's the absolute 15-20 elite brands shedding the Indianas and Mississippi State's of the world to come play in a quite large second tier that has a truly national scope and can organize on regional basis.
The SEC and Big 10 already won financially. It's over. A modicum of clemency would make for a product that would maximize ratings and profitability.