I 100% agree with your 3rd paragraph. Conferences should be geographically sensible. The Pac-12 is the only current conference that, IMO, is sensible. The SEC jumped the shark when they added A&M, Missouri, and Arkansas. The same for the Big Ten adding Nebraska, Rutgers, and Maryland. The same for the ACC adding Syracuse, Boston College, Pitt, and Louisville. The same for the Big XII adding West Virginia.
That's why I liked the old Big XII. I thought it was a good blend of the SW and plains. IMO, culturally, the Big XII should be some combination of: Texas, A&M, Tech, Baylor, TCU, Rice, Houston, Arkansas, Oklahoma, Oklahoma State, Kansas, K-State, Missouri, and Nebraska..........possibly LSU. If you had......
South:
* Texas
* A&M
* Arkansas
* Texas Tech
* Baylor
* LSU
North:
* Oklahoma
* Oklahoma St
* Nebraska
* TCU
* Kansas
* Missouri
.......that's a geographically sensible conference, with natural rivalries. 0.00% chance of happening though.
College sports need to go back to the drawing board, create an institution to oversee them that actually has authority (ala the commissioner's office in the NFL), and divide up into 8 conferences of 9 geographically sensible team, which would leave enough OOC games to maintain any rivalries lost in the division. The winner of each conference makes the playoffs. Simple as that.