I'm gonna go against the grain here and suggest that an F150 with the regular towing package will probably do just fine. Most skid steers are in the 4-6,000 lb range, and a small track hoe is in about the same range. Assuming 2,000 lbs for a flatbed trailer he would be comfortably within the ratings of a truck with the regular towing package. And if he occasionally goes over the rated capacity you can be assured that the truck isn't going to explode.

The basic hitch is rated for 10,500 lbs IIRC, and the max tow hitch only give you an additional thousand pounds of capacity. The downside to the max tow package is the mpg-robbing towing mirrors and 3.73 gears that just aren't needed for the weights the OP is likely to ever tow. The factory brake controller would be highly advisable though, but if not factory installed it's a relatively simple thing to put in.

Not everybody needs the max tow package. My enclosed trailer requires it, but if it didn't I would be happier with a 3.31-equipped truck equipped with the regular towing package.