Knoxville and Nashville have walkable potential in the core, and of course Asheville, NC, but outside of that, the south is as you said very pedestrian unfriendly.
In the Dallas-Fort Worth area of Texas, the city of Richardson is very bike- and pedestrian-friendly. The area around the Univ of Texas at Dallas is especially so.
Oddly enough I’m in Chattanooga and going to Knoxville tomorrow. I’ll find out :)
I highly recommend the UT Gardens, the Sunsphere, Remedy Coffee, and Yassin’s Falafel House if you’re looking for suggestions. Enjoy!