How much are you willing to ?

What is is max load you would pull and still be very very comfortable towing.

I and my '03 2500 Dodge/Cummins truck are very comfortable pulling its 13350 lb tow rating. My truck and myself are comfortable carrying its full max 6000 RAWR. My trucks front axle doesn't carry any weight from my GN ball or 5th wheel trailers pin loads so its not a player in the carrying game , just stopping
I arrive at my pin weights by weighing front and rear axles seperatly and then subtracting my trucks unladin rear axle weight of 2860 lbs from the trucks 6000 RAWR = 3140 lb of payload.

So, what should my maxx weights be and be good for me as well as on my truck.

You can either subtract your trucks scaled gross weight from its GVWR and use that as a max payload on the trucks rear axles/tires.

Or use your trucks axle/tire RAWR to figure how much loads they can carry.

Ford says your '11 F250 6.7 diesel can tow up to a 15700-16100 lb trailer.
Now what your comfortable with I have no idea as to your capabilities and comfort zone. I've made a living with these size truck for many years so my comfort zone tends to use max capacities of the truck that I paid for. As you see others aren't comfortable with carrying up to max loads. Its your call.