The most varied and scenic drive in America is Utah Highway 12 from Escalante, Utah, to Bryce Canyon National Park. This drive takes you through the Grand Staircase and the along the spine of a massive mesa, thus the name "Hogsback." You are driving on top of the world with views and drop offs on both sides of the highway.
Fortunately there is not much traffic and you can see the road a great distance in front of you. Pull offs are few and far between, but I found traffic light enough to just slow or stop on the highway to get quick photos out the open window.