Good idea to do your homework. And stay flexible. We just drove from UT to VA via CO, NM, and I40 through Memphis, Nashville, etc. Took seven days. Perhaps some of below will be germane to your trip.
I hope to do a trip report because we took four really nice scenic drives out west during the first part of the trip in UT, CO and NM. Only one (Canyonlands Natl Park) was firmly preplanned. For the other three (Colorado National Monument, Independence Pass, and Capulin Volcano Natl Monument) I had done minimal investigation and they ended up being excellent activities.
Beware of National Parks. They can be great, but they can be really crowded this year with pent up demand. We had a great and low crowd visit to Canyonlands at 6-9PM.
We got turned away from Arches at 10AM the next day (Friday before Memorial Day Weekend), too crowded. Our next planned destination was to spend a couple of days in Aspen, so I had a vague backup plan to do the scenic drive at Colorado National Monument near Grand Junction on the way to Aspen CO Monument turned out to be a really a nice plan B, with low crowds, great views, memorable roadway, and easy hiking trails.
After Aspen we took the summer-only road over Independence Pass for a scenic route to begin our drive to the East Coast. It was really nice too. We stopped at a picnic area called Grottos and stumbled on a beautiful waterfall/cascade by dumb luck.
View east from Indy Pass:
On the same day we did Indy Pass, we were making our way east and when passing by Capulin National Monument, NM we decided to check it out. It was a memorable last taste of western mtns before hitting the high plains of NM and west Texas.
It helps to have a National Parks senior or annual pass as the parks and monuments have a $20-30 entry fee.
