Thank you Busskipper and Cjoseph...and everyone else!
All very good suggestions.
I totally understand the driving time recommendations. I like to plan my trips with actual road time, not counting stopping for gas or bathroom breaks. Anyhow, I am sure my estimates are still a little too short.
I am still racking my brain on how much to squeeze in. Do I add Sequoia and Yosemite and take out RMNP? Do I add Yellowstone and Teton and take out RMNP?
I think in the end I will stick with my rough timeline, and replace RMNP with a stop at Mesa Verde, Monument Valley, Petrified Forest, or another that is already along the current route. So all the recommendations are well received!
Next will be figuring out where to stay at each location. Do I reserve now? Do I reserve all of them? Or only reserve the difficult ones and leave the rest to chance?