Mack did two 30 minute shows weekly (Rewind with Mack Brown and Game Plan) he also did an hour long show with Craig Way (sp?). You have All Access practice reports which don't require any on camera face time but the hosts often discuss topics with the coaches and do on the spot interviews during some of the practices (5 minutes max). Then there is the weekly press conference, I'm sure every coach has a weekly press conference now days but this was also televised. So that is about 4-5 hours weekly that cameras are in your face as a coach. YES, this is a consideration and a factor to the next HC at Texas. That's why somebody like Mike Leach would never be chosen here, while he is entertaining to watch as an opposing fan I would not want him representing my school on camera that much.
I heard that part of the concession agreement from ESPN/IMG/LHN would be that Saban would be allowed to let his assistants be the headliners in some of the programs Mack was the mouthpiece for. If we are indeed opening up the checkbook for some the best assistants I wouldn't mind delegating this to them.
Additionally, I heard that in the beginning the filming of the programs used to be much more labored. Towards the end the producers knew how to have everything teed up for Mack so that he could get in and out quicker. Remember an hour of screen or camera time takes longer to actually film. Mack had to put up with a lot as the LHN figured things out but it should be easier on the next coach, but that's not to say it won't be without its headaches. They will eventually find their groove with the new HC as well.
To echo what others have said, a personality (resume) like Saban or Harbaugh would increase viewership demand. Briles and Strong don't do anything for interest, IMO.