Hi Rat and Shewie, cheers for the input!
The 'survival kit' is shorthand for a few things I reckoned would be handy - either daily, or in case I got separated from my main kit - I've got to confess I've pretty much lifted it out of the rear pouch my webbing (apart from stuff that obviously won't be required like rifle cleaning kit) - hexi and a spare meal bag from a set of rations, a candle, spoon, spare matches and puritabs, a windshirt, and a few other 'bits and pieces'. Now you mention it that does look pretty irrelevant for hiking and the like in my own time - it's not as if I'm going to have to ditch my rucksack and run from anything, is it, and even if I did lose the pack, the kit would be in it and not on my belt. I rarely use any of the 'survival' part of it, just the everyday items like a spoon. I could probably shave the 'survival' part of it way down, to a firesteel and a few other bits and bobs, rather than the weight and space it's taking up now. As has also been said, ditto the wash kit - no need to shave, yes!
I should probably ditch a set of undercrackers as well - one spare T shirt and boxers and a spare set or 2 of socks is going to be plenty really, most often I come back after 2/3 days having changed only my socks.
I could also ditch the water filter as mentioned and use puritabs, and a Millbank bag would be a good (and relatively cheap and simple) addition too...
I guess what my kit is suffering from is being taken across more or less directly from the mil to the civ side of life, and what might be required in one isn't neccessarily needed in the other (and the timeframes you're likely to be out for are different too). Time to sit down and think about what I really need rather than simply repacking it all out of a bergen and into a rucksack! The 'ticking off what you didn't use' method seems a pretty sound one as well...
As for using a bergen, my original reason for getting a big civ rucksack was to get away from that and not to carry a militant-looking DPM bergen when I'm doing something in my own time, however, now I'm thinking getting away from that is probably a good impetus for sorting out and reducing my kit and getting into a different frame of mind about what I need to be taking and carrying too...