Whittingham. But KS is a good above average D-1 Head Coach. And likely a notch above what Jay Hill would be as BYU's HC.
Kalani, you will recall, was an excellent Defensive Coordinator as Jay Hill is starting to prove he is.
Seems weird to suggest Jay Hill would do a better job than Kalani as BYU's HC with zero evidence.
Weber is not at BYU's level.
I like Hill and I like Kalani in the absence of an available giant. When KS was hired at age 40, he was not ready. Now he is 50 and he is ready. We tend to promote high character people a little too early.
Retzlaff is starting to prove himself. Sitake already has.