If you can swing it during the week while everyone (cruisers) is at work, the Three Twisted Sisters in the Texas Hill Country is worth the ride. Just got to watch for the roaming cows, and cattle grates.
FIFY Nothing like trying to pass a line of 10-15 slow moving pirates on these roads on the weekends.
Literally any road leading out of Eureka Springs, AR.Beartooth pass and north- Mont. I second Hwy 36, Red Bluff to the coast, any of the Three Sisters, (but not on a weekend), and Hwy 550 in CO.Also, ID hwy 75 north of Sawtooth.
You could spend days west of I-25 in CO alone, riding some awesome roads... be doing that since 2007!