I have heard names like Gruden and Stoops but they just do not seem realistic.
The two most realistic names, Dan Mullen and Dan Quinn.
Dan Mullen seems to be the most popular, for obvious reasons. This could be the best season in the history of the Mississippi State program. A team loaded with seniors, so this could be his best year there. Get out and get rich while his value is at it's peak level. Money is not an issue for Florida.
Dan Quinn is another. Current Seahawks DC. Was the Florida DC for two seasons. He has more NFL experience and could be in line for an NFL head coaching job.
Outside of that, it seems sort of open.
If they go the "mid-major" coach route like Auburn did with Malzahn and Ole Miss with Hugh Freeze, it could be Bill Clark at UAB or Justin Fuente from Memphis. I doubt either would generate much excitement in Gainesville but you could do worse.