re: Who would be a whale for Bama?

The whale retired.

No one is going to be at his level, not even at his current age.

The only inarguably elite coach left in CFB is Kirby.

After that its probably Harbaugh but he has the scandal hanging over his head, interviews for the NFL every year, is possibly on the spectrum and would never leave UM for another college job.

So then you're left with a bunch of really good coaches who you can argue reasonably about what order they should be in, all of whom have questions:
-Sark: 1 conf championship, lot of mediocre years before that
-DeBoer: out west ties, never recruited at an elite level
-Lanning: young, no conference championships
-Kelly: no conference championships
-Kiffin: Joey Freshwater, doesnt love to recruit
-Klieman: system guy, never coached at a big time school
-Dabo: Wont deal with the portal/NIL

All of those guys can win a championship at the right school, but any of them could fail at a job like Bama as well due to the expectations, questions and the madness that is NIL era CFB.