Agreed, weight vs. usefulness is always a dilemma.

In my own on-person PSK (a Blackhawk E&E bag) I am very limited with space so I try to stick with the basics. good quality gear, but as spartan as possible.

I do but try to be a little redundant with certain items such as mutiple ways to get a fire going.

I live in rural eastern Kentucky so things like water are not as high on my priority list as there are many rivers/streams/creeks where I hike/hunt/fish.