Pat Sakaj could be replaced with a cucumber and the show would feel the same. If Bob Barker can be replaced Sajak can go and they wouldn’t miss a step.
I will be surprised if they don't take the opportunity to select a qualified woman, probably a PoC. Which is fine. Jeopardy is definitely a show where any stunt casting will backfire. They need plain, reliable, and businesslike.
I was thinking that John Cleese would be great at it... smart, and funny. Word is he still needs cash to pay off his divorce, so who knows?