I'm a little confused as to the purpose of this kit - if it lives in your rucksack then it is a back up to what you already carry, and it's hard to critique without that info. It isn't stand alone

To me a PSK needs to be carried on your person - a rucksack should have all kinds of useful stuff already, the psk is for when things have gone pear-shaped and the rucksack is missing/sinking/on fire/being mauled by a grizzly :-)