Wellllllll---I did ask if she wanted an adventure---but having been born and raised on the Utah side-------I take every opportunity to explore your Colorado Side---guess it is that "grass is always greener" thing. If she is coming from the Northwest---she will get lots of practice going over passes just as bad as Red Mountain so it would not be such an adventure when she got there. I do agree that the tourists slow things wayyyyyyyyy down in July.
Well, I respectfully disagree - ha! If I am telling someone who's pulling a trailer, a good route to Durango, I sure wouldn't send them over Red Mountain Pass - summer or winter. That's an 11,075 ft pass, 2 lanes, a narrow, windy mtn road. Yes, if you're not pulling a trailer, great! But in July, it will filled with slow-moving RV's, tourists, semi's, you name it. (In winter it can be really treacherous, but we're talking about July.)
On Red Mtn pass, there are some areas with no guard rails that if you hung a tire over the edge you could go down a couple of thousand feet. Not my idea of a good road for pulling a trailer to a ride. It would be very slow going, for one thing. Yes, it's pretty, but the roads between Moab / Cortez / Durango are also pretty, they're not as congested, and it's a quicker route.
I've driven to Grand Junction many times from Cortez, and the fastest way (again) is through Moab - certainly not through Durango, and also not through Telluride/Montrose. I do go both ways, and actually prefer going through Ridgeway and Montrose, but if I'm in a hurry, or if there's a lot of snow on the roads, I go through Utah to get to Grand Junction.
Of course, I live here and I'm not in tourist mode -- so, if anyone wants to know some "scenic" routes, summer or winter, send me a line, I love to drive and I know the roads pretty well.