Thats crazy that diesel is so expensive in Texas, here is cheaper than regular 87 octane gas in the summer. Premium 91 octane is 18 cents more per litre than regular too. No way I would give up my diesel for a gasser unless there was an M at the end
Towing with the 35D is great, you won't even know your 2500lb trailer is there.
Get the comfort seats. We have taken some road trips to Quebec City from Toronto (about 7 hours one way), and into Pittsburg (5 1/2 hours). My back is always fine after.
The hitch is always a dealer install, or aftermarket install, but there is a tramsission coooler, and all of the various models are rated to tow 6000 lbs.