This is something I mentioned under a different topic and is in addition to what is talked about under this topic.
Although the Big 12 would be the best fit because of proximity, the PAC 12 may be the next best fit since UH is located in a large metropolitan like 7 of the PAC 12 schools. Flying between large cities is much cheaper that flying to Sticksville U., 600 miles away. Houston would also give the PAC 12 another major TV market.
UCLA - Los Angeles, 13,310,447
USC - Los Angeles, 13,310,447
UH - Houston, 6,772,470
California - Oakland/San Francisco, 4,679,166
Arizona St. - Phoenix, 4,661,537
U. of Washington, Seattle, 3,798,902
Stanford - San Jose, 1,978,816
U. of Utah - Salt Lake City, 1,186,187