I'm not sure why these are the only options. People have towed all kinds of trailers and even cars with their Roadtreks. And quite a few of the Roadtreks have a bed that unfolds across the front seats.
I recommend you follow the https://groups.yahoo.com/neo/groups/roadtrek/conversations/messages Yahoo newsgroup which is very active. https://groups.yahoo.com/neo/groups/pwclassbvans/info (for Pleasure Way) not so active in my experience.
And there are very active facebook groups also: https://www.facebook.com/groups/RoadtrekEnthusiasts/ (which is actually for all Class B enthusiasts), https://www.facebook.com/groups/roadtreking/, https://www.facebook.com/groups/roadtrek/,
Ask your questions there and you'll get lots of enthusiastic advice...