I work as a diesel mechanic here in Alaska, and I can tell you what our company's trucks have. We have oil pan heaters, block heaters, an onboard battery trickle charger would be good too. We have custom made winter fronts on some of them, auxiliary cab heaters to supplement the dash heat, and a pair of Lightforce 240's on the front, also some have additional work lights on the back for hitching trailers etc. during the dark time of the year. A note on the driving lights, Alaskans LOVE good driving lights, Lightforce are widely thought of as the best, but you'll see KC, Hella and various LED bars here and there as well. Some also have studded steer tires, but that really isn't necessary for the average person. A set of tire chains would be nice too. Some of our trucks have heated wipers, and heated mirrors.
Hope this helps.