Bob and Ann, this certainly seems like a good plan to me. While you are in Durango, I hope you can make a drive out to Vallecita Reservoir. Also hope you can spend some time in the town of Ouray.
We consider that drive up from New Mexico into Pagosa Springs one of the most scenic; enjoy the drve.
We have only stayed at the United RV Park in Durango (and that only once.) We enjoyed staying out at Blue Spruce north of Vallecita. But that is a long way out of Durango and I would only suggest it if you could spend some time there just relaxing. There are several RV Parks with full hook-ups around Durango.
I can't comment with personal experience on your route west from Cortez, but all the rest seems good to me. We stayed at a very nice small RV park across the highway from Mesa Verde: I believe it is called (appropriately) "Mesa Verde RV Park."
Sounds like a great trip to me.
Edit to say that your route will take you through Chama, NM. There is a narrow guage railway there as well as the more famous one in Durango.
We usually stay at Santa Fe Skies in that city. Hope you have some time to enjoy that most interesting city.
