I prefer to start out of Big Creek or Cosby. The traffic going through Gatlinburg or Cades Cove can really be bad, especially Fri-Sun.
Out of Big Creek, you can go up the AT (do not skip Mt. Cammerer). You can then loop back through either Big Creek or Mt Sterling(if you want more mileage). I think Gunter Falls is worth seeing. You should know that there is a warning of trail closure on Gunter Fork trail because of landslides, but we were able to cross the landslide easily.
From Cosby, you can go to Hen Wallow Falls and on the Albright Grove, which is virgin forest of massive poplars. You can go up to a bald from there and down Snake Den. If you are feeling a bit more ambitious, there is a longer route that briely hits the AT. I have done this loop a couple times and it is definitely spouse-friendly.
If you want to do some higher ground, you can do a nice loop from Clingman's Dome into the NC side. I forget the trail name, but it will be pretty obvious on the map.
Hope this is useful