Frankly, I think the Big 12 should take several of those schools (the four corners group)
The PAC12 (in my opinion) made a mistake by not grabbing Oklahoma St, Texas Tech and 2 others (potentially to include BYU) last year.
Even though those wouldn't necessarily have added value to the PAC12, it would have ended the Big 12 as a threat. Ironically, the biggest reason for NOT adding (concern that it would dilute the pie and your top teams would then leave) seems to have happened anyway