My fav fun drives in US:
1) Coast cliff side drive from Muir Woods to Pt Reyes. On short list of my top drives anywhere in the world!
2) Fast drive from LA to Vegas, made it in 3.5 hours including a coffee break in Barstow.
3) Phoenix via Sedona to Denver scenic
4) Utah drive up to the Olympic village. Driving through Vermont mountains...
There is nothing special about LA to Vegas!

Some of my favorite roads that aren't in the Smokey Mountains.
1. OR3/WA129 - This is an amazing road from Enterprise, OR to Lewiston, ID. The canyons are epic.
2. Idaho 21 - From Stanley, ID to Boise, ID is one of the best drives ever.
3. Utah 44 - From Manila, UT to Flaming Gorge, UT. Another crazy great road.
4. US 191 - From Flaming Gorge, UT to Vernal, UT. Every time I drive it.....WOW!!!
5. Colorado 139 - From Rangley, CO to Loma, CO. Beautiful and fun with a great drive over the pass.
6. Colorado 92 - From Hotchkiss, CO to US50. This drive is legendary. And the views!!!!!!
7. Colorado 149 - From Hwy 50 to South Fork, CO. Up and over 12k' passes, simply an amazing drive.
8. US 180 - From Silver City, NM to Alpine, AZ. This is another great drive and I never tire of it.
9. US 60/AZ 77 - From Globe, AZ to Show Low, AZ. A great drive with amazing desert views and canyons.
10. Utan 12 - From Torrey, UT to US 89. Views and terrain that are 2nd to none. What a drive.
11. Utah 24 - From Loa, UT to Hanksville, UT. Straight through Capital Reef National Park, nuff said.
12. Oregon 410 - From Sumpter, OR to Ukiah, OR. I was blown away by this small back road.
I could name many more just in my back yard in WA State too! The roads around Mt. St. Helens are amazing.