OK, this is a difficult one to answer without "it depends on...." but here goes. We are looking at a 36' travel trailer, towed w/ a Chevy 3500 crew cab. I have used this truck to tow a 24' boat, plus 3' or so tongue, which is the equivalent of(I think) of a 27' travel trailer. I am concerned about getting around corners if we can't avoid a city or small town. Questions: (1) Is a 36' TT gargantuanly harder to maneuver than a 27 footer" or just much harder? I imagine the turning radius is quite a bit different with 27. vs 36'. (2) Would using a standard cab make much difference over a crew cab? BTW, a 5th wheel is not really an option right now. Thanks to anyone who has experience with such. I'd borrow a 36 footer to try, but doubt anyone is gonna loan me theirs.

 

The Garmin GPS for RVs is great in that the user inputs the length of the tow vehicle and that of the trailer and it routes you to avoid tight turns.
A separate concern is where you can actually put the trailer in a campsite. A private KOA can handle a long trailer but USFS campgrounds will have a limited number of campsites that can accommodate a trailer/RV longer than 29 feet. Check the available camp sites online where you plan to go and see how many long spaces are available. if someone with a small Burro trailer reserves or is first to arrive and takes the only "long" space you will be out of luck.

Overall I would get a shorter trailer that has pull-outs to provide more interior space.
https://www.lancecamper.com/travel-trailers/1995/