He mentioned a garage, which is better than an extended cab I think. Though I have a bicycle and tons of storage in the back seat it isn't ideal due to its shape, door size, and the door not opening all the way. Do the Fords have suicide doors? That would help some. Also there is a decent amount of space behind and between the seats in a single cab, to store things you might want while driving.
So been thinking and researching a bit... like the idea of a F450 single cab with a 169" wheelbase, super singles, 38x13.5" tires, suspension upgrades, pivoting mechanism, garage, under bed, and side storage, and low platform for a 8' slide in camper. Could design it for a flatbed camper too, if desired. The tires would limit you to a little over 8k lbs on the rear axle, but that shouldn't be a hard target to hit. Huge step up from a half ton anyway, while still being very capable offroad.