I think Ken Jennings would be a good choice, but he'd need training, since he's a bit too "Aw Shucks" to carry the program right now. Brad Rutter would be better - he's faster, and more personable, but he's a smart aleck. James Holzhauer is way smart, but much too smug to be a game show host. They're three brilliant game players, but announcing and hosting a show like Jeopardy requires a certain degree of finesse. The host has to have an air of smarts, combined with a certain sense of urgency. I have no idea who could do it. Let's hope it's not Steve Harvey - with his screwups at the beauty pageants, he'd be a mess by the end of the first show.
Wait - if Wink Martindale and Pat Sajak had a love child...
Dave