Here's the straight scoop. I ran gas trucks most of my life because the truth is, diesel pickups do not math out. I ran the numbers over and over for years and years... the fact is gas trucks cost less overall even with less MPG.
The reason I finally bought one was POWER, and reliability. Mostly power.
I know several fleet owners that run one-tons, one is a tow company, that figured this out years ago and runs all gas trucks. The accountant isn't lying.
My diesel cost way, way more than I ever wanted to have into a pickup truck, (I've got more $$ into just the transmission than I wanted to put into a truck!) but it does make over 400HP and 800 ft/lbs, and I can turn it up further - a lot further - if I want and it does get twice the mileage as my 454. It goes a LOT better, but it does not save money.
The only other thing is resale value, especially when gas is high, is horrible on a gas truck. No one wants it.
But if the gas truck is your choice, don't worry about its ability to haul you and all your stuff. We're all spoiled on crazy torque and have forgotten that Hemi is far stronger than anything you could buy not so long ago.
Dig up an old issue of Trailer Life from the early '70s... everyone used to tow with their cars!