I'm sure you already know but, the ride from GA up into TN on 129 is a nice ride! Obviously, there's the Gap along the way for better or worse. You could come on up my way and come through 421 and head up towards Damascus and keep going on to Grayson Highlands at Massey Gap. It's much like Colorado up there. Then you could head towards The Back of the Dragon on VA16 which is a really nice ride then work your way on up through VA into WV and swing into Pickerington, OH. to the AMA Museum.
Out in CO, you should hit some of the back roads around Red Cliff, CO! Wonderful mountain roads with old dead mining towns and beautiful scenery! The bridge at Red Cliff is used in a lot of car ads.
Once you hit NM, TX, OK, you could hit Route 66 for a bit and of course, you have to visit Cadillac Ranch! There's a little shop just before you get to it that sells spray paint so you can make your mark (however temporary it may be!).
One thing I wanted to do so badly on my cross-country journey was camp in the median clendestinely but, the opportunity never really ocurred except once and it would have been epic but, the timing was wrong
The next time I take a big trip I plan on it!
Will you be posting a blog or anything of your journey?