I think your smart looking at class B’s. This past May and June I took a +12,000 mile road trip up through Alaska and Canada using my toad (a 2005 Dodge Caravan with a sleeping/storage platform in the back). My Class A’s 7mpg made doing the long trip in it cost prohibitive. During the trip I met a woman from Homer Alaska doing a similar road trip in a late 1980’s vintage Class B. What a neat set-up she had! What impressed me most was that nearly everything in it could be multi-tasked. It had a sofa bed so that the bedroom became a living room during the day and with a fold down table it could quickly become a dinette. It had a shower pan in the hallway floor between the front and rear. Just lift the cover off the pan pull out some plastic curtains and you had a shower. It had a head, an elec/gas refrigerator, and a small 2-burner range top. The front driver and passenger seats rotated and became easy chairs.
For any RV multi-tasking is paramount, but especially in a small Class B.
Steve