A great 'theme' for your tour, IMHO...National Parks, especially ones in the West. They all are NPs for a reason and will knock your socks off.
I'm thinking you guys will be moving from place to place regularly during your tour, so you may want to consider a used class A motorhome. From what I've observed, an 'A' will take less time/work setting up camp and breaking camp. However, if you will be spending more time at destinations, the 5'ver may be a better choice...less complex and I think, more room.
When we started, we wanted a fifth wheel, so we went to a local campground and watched people setting up and breaking camp. Didn't take long to see that the 'A's won in that department. Still, we checked out tow vehicles and found that $65K was the going rate(2010) for a decent TV. We never looked at 5'vers seriously afterwards.
We knew we would be starting out in the 'travel mode', so we decided on a five year old, clean HR Vacationer 36' gas class A with 17K miles on it for less than a 5'ver tow truck...their out there.
In the next 4 years, we traveled to 49 states, 3 CA Provinces, and visited 38 National Parks(two in Alaska). Your mileage may(will) vary...much to think about - lots of choices, so have fun with them and