I want something that I can sling over my shoulder, and also attach to the front of a couple of different rucksacks. I don't especially want this "gunslinger" style, but don't object to it.
Its, just got to be big enough to carry the things that I seem to use regularly, e.g fire starting kit, multi tool etc, and stuff that I hope never to use, but want to know I have with me .e.g first aid for burns and cuts. Something I can take on a walk, but also something I can grab to take into the garden when trying out a new stove, knowing that the key things are all in one bag.
I've thought of a Snugpak response pack, but I would rather have something vertical to attach to a rucksack, and it may be too big. I've also thought of a gas mask case, but much as I like these, I feel that something more modern is likely to have better fixing options, better at dealing with rain etc.
However, at the moment I haven't ruled anything in or out, so any pointers would be appreciated.