Do the bike ride through Cades Cove. They used to close Cades Cove to cars/trucks so that walkers and bikes could use the road on certain days. Check at the Ranger Station on the North side of the park for details. Get to Cades Cove early in the morning to see the deer/elk herds feed in the open meadows. Also, take the hike up to the top of Clingmans Dome, located in the parks at the TN/NC state line. On clear days you day see for miles. Also you can do the hike up to the Chimney's. From the south side of the park, head towards Bryson City and continue west on 19 to the Nantahala Outdoor Center in the Gorge and maybe do some white water rafting. It's a very wonderful drive and I recommend getting an early start, but it's a doable drive in 1 day with times for stops.