4 Texas teams in Big 12.
4 California teams in Big 12.
Doesn't matter if you're a "charter member" or not. California, Texas, and Florida are all big enough to handle 4 teams in the same conference.
If I had to choose between UCF and USF, I would choose UCF. More growth potential and would really be a thorn in the side of UF and FSU when it comes to recruiting.