IMO, 32 foot is perfect.
However, if I were to go full-timing again, I would want a washer/dryer, so I would have to get a 34 or 36 footer to have the room for it.
I am very happy with my Ford V10 powered coach. We towed a PT Cruiser on a dolly from Montana to Tennessee (well, OK, Georgia, actually, near Chattanooga).
No problems at all.
I recently made a trip from Billings to the Flathead Valley and back, towing the Dodge Ram 1500 over the Continental Divide. No problems.
DW just came back from a trip to Thermopolis, WY, towing the Dodge. No trouble.
Personally, I find the ride quality in our Southwind to be perfectly adequate. But then, I don't expect Rolls Royce ride in a heavily loaded truck!
As for "fuel economy", IMO using that term and "motorhome" in the same sentence is an absolute oxymoron! If fuel economy is a major concern, one probably should not even be considering a motorhome.
