How hilly is your terrain, and how often do you pull the trailer?
Mostly flat and not pulling often = 1/2 ton, although you might occasionally be annoyed with getting going slowly with the trailer.
If hilly and/or pulling often going for the 3/4 for more consistency would be better.
It is like picking between economical hatchback. Being low powered isn’t generally a big deal if you aren’t loading the back with heavy stuff and driving around flat roads, but if you use the hatch to move a few hundred lbs a few times a week uphill then getting one with a more powerful engine makes sense even if the hatch size is the same.
The biggest advantage to diesel in my outdated experience was low speed torque for heavy loads, especially trailers.
Oh, and you will wear out a truck where you regularly pull the max load a lot faster than one where you regularly pull closer to half the load. Those max loads are not intended to be regular.
Wasn’t sure if your first year was representstive of future years.