We have both a diesel Ram 2500 and a 4runner and spend a lot of time in a small western CO mountain town that sounds very similar to yours. On our dirt road and local trailheads, I see the same three types of vehicles over and over: Ram HD trucks, 4runners, and Subaru Forresters.
If you're considering a slide-in camper, go 3/4 ton at a minimum, 1 ton would be even better, but don't waste your time with a 1/2 ton. If you're going to carry sleds, check out a sled deck so you can can bring your buddy's sled and not have to mess with trailers or fill up the parking lots with extra vehicles. Both a sled deck and a slide in camper put weight up high and will benefit from similar suspension setups. An 8' bed would be ideal for a sled deck or slide-in camper but a 6.5' bed can be made to work.
As far as the truck vs 4runner, I like having both. Obviously the truck does great w/ campers and sleds, but it's also nice for hauling firewood, gravel, construction materials, trash etc. Things that are inherent to rural living. The large cab is great for families (but maybe not necessary from what you describe), 35's fit on the stock suspension and a turbocharged diesel is unphased by high elevation. However, short drives (<30 minutes) in the winter are pretty much the worst possible diesel use case as you won't be getting any heat in the cab and it's tough on the emissions systems.
The 4runner is easer to maneuver in town and on the jeep trails in the summer, handles better in the snow vs an empty truck bed, and the cargo area is heated. The heated cargo area is great for dogs, ski boots, etc whereas on the truck lots of stuff goes in the bed and gets cold. A topper on the bed keeps the snow off things, but then you're juggling taking it off whenever you want to run a camper or sleds. I don't worry about if I end up in a snowbank with the 4runner and someone has to pull me out, but I do worry about it with the truck because of the extra weight. I think the 4runner on 32s has the same if not better approach/breakover/departure angles as the truck on 35s.
What if you keep the 4runner and buy a beater plow truck? It can push snow around, get your sleds up to the pass, and haul firewood but you'd still have the 4runner for longer trips and summertime.