You've come to a really good source of info, and can use the search feature, too, for destination/campground suggestions, or random questions that pop into your mind.
It's also good that you have lots of time for research and trying out ideas before buying. If possible go camping with a friend or rent an RV for a week to do a hands-on tryout.
I've met many singles and couples who full-timed in Class B camper vans with their bikes racked on the back. Bs are very pricey new but have good re-sale value, and there are more used ones out there now that they have gained a lot of popularity. The advantage is you can always find a place to camp, and your RV doubles as your vehicle when you want to get groceries or see the sights (with all your stuff handy). Fuel mileage is far better than other RV options. We loved our diesel class B.
You mentioned the Southwest, and that was our first long trip after getting an RV. It's still my favorite area in the US. Buy the AAA Indian Country Guide Map online - it's a great reference map for the Four Corners area. Plan to take the free tour of Crow Canyon Archeological Center near Mesa Verde NP (or better yet, do their full day class or longer) to learn about the area - it gives you insight into the whole region's ancestral puebloan sites like Chaco Culture National Historical Park, Aztec Ruins, Mesa Verde, Hovenweep, Canyons of the Ancients, etc.
And then there are Utah's fantastic National and State Parks. You'll have a great time exploring!
