Whether you buy an F250 or F350 is more a function of tags, insurance, toll ways, parkways, parking regs, homeowner association, hammer lanes on interstates, blah,and blah. A lot of this is a Northeast USA set of things.
You can as others have posted, set up either truck to be as soft as possible, yet still carry the load. That is if the door sticker weight means anything to you. I think you should weigh the trailer loaded to know what you really need.
I am pulling a 9600# (scaled weight) fifth wheel. I use a 2022 F250, with the camper package, 7.3 gas, 4:30 rears with an auxiliary gas tank so I can go 500 miles between fills. Works well for me. It rides rough with the camper package (overload springs). It is also good in the mud. It is within all the door sticker weights.
My previous truck was a 2012 F250, 6.7 diesel. I do miss the power every once in a while, but the gas job is a little better in the mud. Tradeoff and compromise, plus saved some money.