Have a 2017 f150 fx4 with the coyote v8. I love it except trying to park it. It has the turning radius of the titanic. However the v8 in it is sweet. If I were going to buy another, I would get the 5ft pan instead of the 6ft. Other than that put on an icon suspension and some good 33s and have a ball.
I'm always shocked how many truck-drivers don't know how to park them. I'm not saying you don't, I just find it interesting how often parking is considered the issue. Then again, I prefer to park at the far end of parking lots in end-spots anyway (even with my old-turd WJ) so I don't find myself squeezing into "traditional" side-by-side spots too often.
Still, when parking a truck, there are 2 main tricks. If you must go in forward, you initially aim like you're parking in the spot past your intended spot, even 1.5 spots past it depending on your wheelbase. You pull up as far as you can toward that next spot, cut the wheels all the way the other way, then back up. This puts the tail of your truck inline with your intended spot, and you just pull right in. I even see people with larger sedans or minivans struggling with this all the time. It blows my mind nobody ever learns this. The other trick, well, just back in. ;)
I would go with a F250 Gas. Diesel will add 600# plus and I don’t know that gets out of the shop for less than $1500.00. The reason the F250 cost so much more is the build, they are far more robust.
Unless you're keeping the truck fooooooooooorever the resale on the diesel truck will easily offset the slightly higher maintenance or repair costs (unless it's a 6.0 or 6.4 PSD). As for the weight, it's a relatively small percentage of the weight of the truck, and I don't see it as a big issue. I suppose if you sink it to the framerails in thick mud, it's a problem... but then, you have other issues at that point.
F150 is a car with a box easy to exceed the GVWR.
F250 is a truck, heavy frame, heavy axles, lots of payload.
All that counts is which one is rated to carry your stuff.
And how tough does it need to be. I'm hard on vehicles, I'd never buy an F150.
Diesel vs Gas.
Depends on what you do. The diesel is a towing dream but unless you need that towing capacity, save the $$$ and go gas. Lighter, cheaper to maintain, better in extreme heat or cold. Modern diesels are frightening in remote locations.
I'm not aware of a car currently sold in the US that's still on a full-frame platform. I'm also not aware of a car with a real transfer case, low-range, etc. I'm not even a Ford or 1/2 ton guy, per say, but it's pretty silly to call them a "car with box." If properly optioned they have a decent GVWR ceiling for Overlanding (more CCC than most SUV/cross-overs we see for Overland use).
What is frightening about a modern diesel in a remote location that is NOT also frightening about a modern gasser in a remote location? If you want ZERO dependence on electronics, you want an old 12V Cummins (but even that is going to need a starter... so you're never 100% electricity-free). If you look at a modern diesel and then an engine like the Ecoboost twin turbo V6s in the F150s, both are extremely complex with tons of electrical systems.
Also, what is bad about a diesel in extreme heat or cold? I've towed 15k+ lbs in over 110 degree ambient temps with my diesel and it stayed cooler than the gassers that weren't even towing in the group. Extreme cold? Well all engines I'm aware of use oil, so at a certain point you'll want an engine block heater in either. Yes, diesel fuel will gel in extreme temps, but they have additives to prevent that.
Anyway, my point here is that a person shouldn't pick gas or diesel based on random preconceived biases about them (including mine). The reality is, a person should pick based on things like the capabilities they need, resale value, etc.
-TJ