Yep, I usually get a good laugh at Doomsday Preppers, too. And just saying, if I had those kinds of supplies, I don't think I'd want to be filmed and viewed around the country... But I'd say get a good compass, and ditto on the couple ways to purify water/start fires. And I have some 1,200 calorie Mayday food emergency bars in mine, they have a long shelf life, can be stored in extreme heat or cold, and don't make you very thirsty (from my experience). I get mine from Camping Survival, prices are cheaper than Amazon! 
1200 Calorie Food Bars, Apple Cinnamon Flavor
1200 Calorie Food Bars, Apple Cinnamon Flavor