It is obvious that not all F-150s are the same. My 2011 E-boost 4x4 with the tow package is rated for 1411 lbs. max cargo on the sticker.
I lost 200 lbs. of the cargo capacity with the fiberglass cap. I do get 15 to 16 mpg in town and an honest 19 to 20 on the highway. It is my day to day vehicle also.
The F-150 is a great match to my 25 ft Dutchmen Lite and though the CAT scale shows I am at or near its recommended weight limit. It has provided consistent performance for over 11,000 miles of towing.
So it would think a 1700+ lb. payload would be a good match for a TT with 1000 lbs. of tongue weight.