If this is not your daily driver and will be used for less than 400 miles per month you should just be looking at it from an economical standpoint. What TV will handle your cargo and TT best? You will never recoup the money on a Diesel but it will hold its value better.
I get better mpg than I did with Gas, but the Diesel costs more. I come out maybe slightly ahead on gas. On the other hand maintenance is more expensive. I just had the oil changed for $100. That 10 qts of synthetic diesel oil...
If it were me, I would get a 3/4 ton gasser and forget about it. However if you are thinking of longer trips at all in the near future. Then think Diesel. My Duramax van barely works going up hills where the same van with a 6 L gas struggled. I upgraded to Diesel to help with cross country trips where crossing the Rockies with my gasser could cost me significant time.