I think it will be a while before you see that breakdown, because every school in the country is looking to do what they can to advance. Every Sun Belt team would leave for C-USA right now, every C-USA would leave for nBE or MWC, etc. Until all the chips hit the ground and the dust settles, then you might see some regional conferences form out of what's left of the MWC, Sun Belt, and C-USA.
I think you will see a conference west of the Mississippi plus USM, and another with the East teams from the Ohio river down (with a small chance of WKU and maybe Marshall being absorbed by the MAC).
You would be looking at:
WEST:
UTEP, UNT, Texas ST, UTSA, Rice, Tulsa, stAte, ULL, ULM, LaTech, USM
EAST:
UNC-C, UAB, Marshall, MTSU, WKU, FIU, FAU, ODU, Troy, USA, GaSt.
I don't know that I like it, but I certainly don't hate it. It probably won't happen anyway because some of those schools are hell bent on keeping each other down, and travel would be too easy.
EDIT: Added a pic for dramatic effect:
sbsusasplit.png (Size: 195.44 KB / Downloads: 18)
Double edit: I just realized how football centric the west would be and bball centric the east would be. It is funny how geography impacts sports emphasis.