I know some folks who have great first aid kits, I mean top of the line stuff. And unfortunately for them they have never taken a first aid class. I would rather they have taken a single first aid class. Training trumps gear!
Oh, you picked up on the “…second most valuable…” part! Yup, good catch. The first good skill set I think you should have is self-defense. Sure, it can be the martial arts kind if you want, or even a knife fighting class. But I would much rather you be proficient with a pistol, carbine and shotgun.
A great first aid kit, food & water storage or any other “prepper” gear won’t mean a thing if you can’t defend yourself and your family. Learn more about setting priorities by reading SURVIVING ANY DISASTER: Part 2 – L.I.P.S. (Priority Setting)