X2 to each of the 3 previous comments. We have just arrived at Jackson, WY, from the 160/191/89 route. Except for a 20-mile stretch, 160 is an excellent hwy. We consider Monument Valley as a "bucket" destination.
Hwy 191 is another pretty good road. Once you arrive in Vernal (Dinosaur country) recommend that you make the 104 mile drive up to Rock Springs as a 1-day effort. The Flaming Gorge National Recreation Area is beautiful + you will climb, climb, climb, over 3 mountain passes.
The best treat is the Hwy 191/89 drive from Rock Springs to Jackson. No mountain passes to climb like the previous day. Once you arrive + pass thru Boulder, it is green, green, green. The decent from Pinedale into Jackson is a beautiful treat.
Enjoy.