Looking at 2017 F150 XLT Super Crew with the 3.5 V6 GTDI Eco Boost and new 10 speed. It looks like it can tow and has the payload for our 30' Heritage Glen with dry weight of 6400 and 7500 with gear, ...
You will have no trouble with power. The engine is the closest you will get to low rpm diesel torque in a half ton, especially up hills!
I am at about that weight (a bit lighter) and 5' shorter. I don't question my setup, but do realize I am at the limits of the half ton platform. Mind you, engine is not in question, the weight of the truck may be (even more so with your extra length).