They won't have too much bother. Dallas/Fort Worth and Houston are the two most fertile recruiting grounds in the country. Scouting boards for Houston alone have over two hundred players who could play 1A.
UT have Scrooge McDuck money for someone to build their program. Plus, Mack held on long enough that the last couple of years haven't been that great, so the pressure isn't that much. The media obligations are a pain in the balls, but not a dealbreaker.
The Big 12 may have lost some lustre (it's no Big 10 though...), but with the four team play off it probably represents one of the more straightforward routes to the big games if you win your conference match ups.
I said before I don't believe Saban would take it, but they won't have a lack of big time interested candidates.
I think Gary Patterson would be a great coach for them, although he always portrays himself as a TCU lifer. I think Jon Gruden would feel hampered by the time restrictions in college ball and prefers the pros, but imagine it as an out of the blue option. David Shaw? Hell, if they wanted Muschamp, I'd run to the job if I was him. Make sure I got me a decent OC and then set about teaching these kids how to tackle.