Yes, this is sounding much more realistic. My parents used to do that in an old Caravan years ago and had a great time. The Transit Connect would be just about ideal. The new one comes in two lengths. Unless you’re very short you’ll want the longer one. The old Transit Connect came in a single size, about halfway between the new models, and long enough for most people.
Towing in the high mountains wouldn’t have been a lot of fun. Getting down the interstate might be OK, but you also have to maneuver the narrow roads in campgrounds and back into camping spaces (assuming you use Forest Service campgrounds, which you will want to, as they are often the only places to stay in the most beautiful areas.) No fun at all.
The problem with using a light duty vehicle for towing isn’t just the lack of traction, it’s that power is substantially reduced high in the mountains. For turbocharged engines it isn’t reduced nearly as much, but it still wouldn’t be fun to tow a trailer over many of those passes with a low-powered crossover. If you can take a little more roughing it, I like your new solution better. You can take it anywhere with ease and not have to worry about a trailer. Parking it in towns becomes no problem. Q You can make it as comfortable as you like with insulation and a comfortable mattress. I spent my childood vacations sleeping in the back of a station wagon and have great memories. Mosquitoes were a problem. Get some mosquito netting that you can drape over the doors before you close them. Then you can roll down the windows and they can’t get in.
This was never much of a problem in the high mountain areas. They do have mosquitoes, but only for a short season and they were out around sundown. Later at night it was too cold for them. Also too cold for you to have windows down. We had plenty of mornings in mid-summer where the temperatures were below freezing at dawn. I’d do whatever I could to insulate your van. Shouldn’t be very hard. Combined with warm bedding and you’ll be comfy. Just sleep in on the really cold mornings. We all resented my mother trying to get us up and moving early when it was freezing, especially since we knew it would warm up quickly.
I envy you so much. This is exactly the kind of trip I’d love to take. I was at many of these places as a kid and have been back to some, but not often enough. They are so gorgeous and you will never run out of interesting places to go.