We did same trip in 6 days

My wife and I also try to do many states in one trip since travel is expensive. We did the same 9 highpoints trip in 2006, but in reverse order. I am amazed by the people who have done 8 highpoints in 24 hours. They must have known the roads well and had no delay problems. We also found that it was difficult to get anywhere fast on the curvy roads in that area. We got held up by a coal truck accident, road closures around Mount Mitchell, and trail closed at Clingmans Dome due to visitor center construction.

Here is a brief description of our trip:
4-08-06 Flew into Atlanta
4-09-06 Visit Georgia Aquarium in Atlanta, climbed Brasstown Bald via Jacks Knob Trail, stayed in Blairsville, GA
4-10-06 Climbed Sassafras Mt. via Foothills Trail, climbed Mount Mitchell via Old Mount Mitchell Trail, Stayed in Asheville, NC
4-11-06 visited Biltmore Estate, climbed Clingmans Dome via Forney Ridge Trail and AT, stayed in Asheville
4-12-06 climbed Mount Rogers, climbed Black Mountain, stayed in Norton, VA
4-13-06 visited Hatfield Family Cemetery and Museum near Beckley, WV (my wife is a Hatfield...really), climbed Backbone Mt., climbed Mount Davis, stayed in Seneca Rocks, WV
4-14-06 climbed Spruce Knob, climbed Seneca Rocks via hiking trail, stayed in Seneca Rocks
4-15-06 Flew home out of Roanoke, VA

8 days should be plenty of time to do the highpoints and to relax and see some of the other attractions of the area. I would recommend including Seneca Rocks in your trip. It is a pretty area. Have fun!