Always, always order the heavy tow group. Best choice either for resale or possible future use. Better cooling and most of the time more items are upgraded than is listed. Great value from the factory. Adding a hitch afterward and wiring is not even close to the factory package.
Not only do you get the beautifully mounted and tucked in fully engineered trailer hitch, but all the electronics that go along with it, and the extra cooling for engine and transmission. You get the integrated dual plug in for lights and trailer braking and tow/haul button on the dash.
You will most likely never get back the money for resale, but if someone wishes to purchase your jeep to tow, it will most likely seal the deal.
Your jeep will also come with automatic sway control that adds braking force to individual wheels to dampen a swaying trailer.
Very well integrated towing system for just a bit more than the cost and hassle of installing a aftermarket hitch.