Greg Byrne is at the very top of the list for me if we're finally filling that void. I was really uncomfortable with permitting Perrin to continue serving as his AD. While very successful, I couldn't imagine him actually fulfilling the duties of an AD without any prior experience. Not at Texas.
What Byrne has done with Arizona is pretty amazing. He has made all of the right coaching decisions, even if Rodriguez's seat is getting warm. He has a PAC-12 South Title, a baseball national title and continuous great performances from the basketball team.
He was also great at Mississippi State. In addition, I personally think Arizona has marketed their program exceptionally well since Byrne's arrival.
The idea of hiring Mack doesn't bother me. It doesn't necessarily instill great confidence in our programs trajectory but the man is accomplished and all you have to do is look at Nebraska as an example of how a former coach can prove himself to be a great AD.