Gary PM'd me about this, and I hope to be able to join you.
Either going or coming, you might consider a stop at Paradise Gardens in Penville, the home of the late, but IMHO great, folk artist Howard Finster. I've been there a number of times (it's on one of the Huntsville-Atlanta scenic routes), but haven't been since he died. We plan to stop by and see what shape it's in.
The Lookout Mountain area is full of possibilities: Cloudland Canyon, DeSoto Park, Little River Canyon, and Sandrock, another "rock city" similar to Rocktown.