Well definatlly if your looking at pulling the diesel is prolly better than a gas pending on what engine's your looking at for differnt rig's,personally i wouldn't have a diesel,there loud and very annoying. gas engine's are much quiter till ya dump a good set of mufflers,gas engines would be pretty much a mid point,give's your torque/horsepower and move rpm,bumping a diesel up can give your massive amounts of torque,but that's about it,unless your pulling a toy hauler,or a heavy weighted trailer,go with the gas,it will haul both and when your start it up in the morning,it won't wake everybody up.
Ford's are my pref,chevys are ok but the comfort blows. As for dodge,never really been a huge fan,i would check consumer reports,i myself have never seen anybody have problems with a ford or a chevy,but i have freinds that worked on dodge trannys a lot,everything I've heard about the trannys isn't good,they don't last long,they don't shift right and there overall a p.o.s,look into what your buying, some consumer and buyer reports can be B.S