The Big East as a 3 team football league is a pretty solid idea.
I'll try to improve on Bob Ryan's "original" idea...
Big East- BC, Uconn, Cuse, RU, PSU, Pitt, WVU, VPI, ND, UM
Covers the Northeast Corridor with rivalry pairings up and down the entire lineup. Includes pseudo NE Schools ND and Miami which recruit heavily from the area and have a good presence within it.
ACC- UMD, UVA, WF, Duke, UNC, NCST, Clemson, USCe GT, FSU
Covers the Southeast Portion of the US with rivalry pairings.
SEC- UGA, UF, UT, Vandy, UK, Ville, Bama, AU, Ole Miss, MSU
Covers the SE and Deep South with rivalries throughout the entire lineup.
Big 10- UM, OSU, MSU, UW, IA, MN, IU, PU, IL, NW
Its the original Big 1o. No need to screw with it.
Big 8 +2 OU, UNL, OSU, KU, MU, KSU, ISU, CU, Cincy
A bit trickier after 8. Added Cincy as they are technically Midwest and carry a P5 AD. For # 10 I'll add Tulsa strictly for geographic purposes, but another top MAC School like N Illinois or Conf USA Program like Marshall could be an add here. A lot harder to find worthy programs and geographic fits in this portion of the country.
New SWC- UT, A & M, LSU, Tulane, AK, TCU, TTU, Baylor, UH, SMU
The majority of the Old SWC reunited with the addition of the State of LA makes for a powerful and geographically cohesive conference. This would be a rugged conference to win.
New MWC- BYU, Utah, BSU, Wyoming, New Mexico, CSU, UNLV, SDSU, FSU, UH
A geographically spread out conference that touches on areas throughout the Western US. Not a powerhouse on the field, but needed if you want to put on a tournament that is inclusive of the whole country.
PAC 10- UW, WSU, OU, OSU, USC, UCLA, Stanford, Cal, UA, ASU
The old Pac 10. No need to mess with it.
Obviously there are some notable omissions on here such as UCF, USF, Temple, Marshall, The Service Academies etc. That said it would be cool to have real geographic based conferences each loaded with multiple rivalries. Each could crown a champion and send them to a real non biased 8 team playoff.