For such a short backpack, just about anything works. If he wanted to carry 70 pounds and have tons of creature comforts, I find that totally justifiable given the distance. Once you get into longer trips (such as 10 miles in a day or multiple days) then you need to minimize the stuff you bring. Different strokes for different folks; different gear for different goals. Also, different environments require different items. I do not think there is a valid generic "list" that applies to everywhere and all seasons.