Your needs do not require a long bed. I have been towing several FWs, using 6'9" bed Ford trucks for going on 20 yrs. Fords axle center, to back of cab is about 41 inches. I've been using non-slider hitches with my Fords, and currently 1" ahead of axle center. With the newer contoured fronts on the FWs, a standard bed is a non-issue. Also most modern FWs have somewhat extended pin, adding extra clearance. You could hit the cab under the right circumstances, if you worked at it, even with a long bed. Just using common sense/awareness is required no matter what your towing, TT, boat, cargo trailer, or FW.
Just another thought...a long bed crew cab truck will require more space when maneuvering/backing a FW, due to the longer wheelbase. My SC with 142" wheel base helps for this, and is also a very stable platform while towing.
Jerry