Just like with cars, you never, ever want to trade in or sell something and still owe money on it. (I cringe when I hear people who do this...bringing a $30K car loan up to $40k or more.)
We, also, discovered we loved camping a LOT more than we had originally expected and around year #2 started to look at other types to upgrade to. (Everything from Class-A's to 5th wheelers to TTs.)
Finally, at the end of last year, we found the Rockwood at our originally dealer and we only owed $10k on the old TT and he was willing to give us $14K for it AND he discounted the Rockwood to a super-low price for us because he wanted the room for the new models coming in.
Good luck in what you decide!
Rick & Karen
(Retired USAF, MSgt)
5-year Travel Trailer RVers
2013 Forest River Rockwood Ultra-Lite 2904SS
2014 Toyota Tundra Maxcrew SR-5 TRD 4x4