Every Tow Vehicle should have an auxiliary transmission cooler. For the couple hundred dollars it will cost, it is cheap insurance.
Any trailer with a GVWR of over about 4000 lbs should use a a weight distribution hitch. That trailer is on the borderline so I would spend the money for the hitch.
Hybrids do give you a lot more living space for the same weight. Fall and spring camping will be chilly so take extra blanks. If you are going to have an electrical hook up, most people use an electric heater. Save your propane !