Since you mentioned you pull your horse trailer all over ID, I assume you are contemplating pulling the trailer with the camper installed as well?
If that is the case....
You should look at the Ford charts and graphs and see where the torque curve is relative to engine RPM. If you are constantly operating the truck's engine in the top 1/4 of the RPM band to pull the trailer and the payload in the bed, your engine's life span will be greatly reduced. Gas engines simply aren't designed to constantly operate in this range. Not only are you generating a lot of RPM, but exhaust heat as well. Even more so with the twin turbos. Gas engine EGT is not nearly as critical as monitoring diesel EGT.
Another factor to consider, your 10 speed transmission is going to be constantly shifting (even more so then when simply pulling the trailer) to maintain chip parameters. Not a bad thing, just something that can get a bit annoying on long trips listening to the tranny shift at any slight grade change.
For what you're trying to accomplish, is why many folks prefer a diesel engine/truck. Heavy payloads, towing heavy loads are what diesel trucks are designed for.... I'm NOT suggesting you go off and buy a new diesel truck!
Ask around and find a reputable truck upfitter in your region. I'd drive over and have a chat with them.