Just some comments....
A) We have a 42 ft and have never been turned away from a state or national park.
B) As other posters have stated, the floor plan is of utmost importance.
C) High on your list should be Aqua Hot and a "stack unit" washer & dryer.
D) Ours has a Tag Axle and is really a dream to drive (no porpoising and handles wind really well).
E) There are so many decisions to be made and only the two of you can make them. Make a list and hold to it.
2008 Monaco Dynasty, 42ft, 4 slides, 425hp clean air Cummins diesel
2013 Jeep Wrangler Sahara Unlimited w/M&G Braking System
Roadmaster Blackhawk 2 All Terrain Towing System