I haven’t done your exact path, but I have done ATL to Panama City Beach to Orlando, and separately I’ve done Pensacola to ATL via Montgomery. I can see why there’s a number of other people around here who drive through Dothan, AL & pick up I-10 at Marianna, FL.
The theoretical map-app time for the three main route options, going through ATL, US280/GA520 (Columbus), or I-10 (Dothan, Marianna) are within 10 minutes of each other. Dothan/I-10 is 25 miles shorter than the Atlanta route. The Columbus route is an additional 30 miles shorter, but you’re on 2-lanes / off interstates for the longest. Since I value avoiding Atlanta (unless I have a reason to go there… like the Aquarium), heading down to I-10 and taking that to 75 is the way I’d go. I-10 is also quieter and more pleasant than the stretch of I-75 you’d be avoiding in south GA / northern FL.