If you are a hammocker, the Smokies AT is not a good choice. It's a shelter-bound area requiring reservations for each night.
My advice would be start at Mt. Rogers National Recreation Center HQ and hike the AT south through Grayson Highlands to Damascus. Wonderfully cooler temps than much of the southern AT that time of year. Also, it's easy to park in Damascus and get a shuttle to MR HQ.