Couple of thoughts as I was reading this thread.
Components -
Milk powder. Tastes a bit weird on its own, but it'd be great for teas, sauces, cereals, and porridge.
Oats. The flaked ones. Can add bulk to soups, but will be best in porridge. Also adds fibre to any breads made with it.
Flour. If you're into baking at all. Can thicken soups for a little added carbohydrate. Maybe take some veggie suet and make dumplings for all the soups.
Chocolate powder. For making hot chocolate. Maybe you want to add it to porridge, or make some kind of flapjack with the oats. Very light, you don't have to take much, but it'll be lovely next to the fire with a mug.
Boullion. Powdered, I like the 'Marigold' brand stuff. Very strong so a little goes a long way. Great for adding taste to any native greens you may boil up - like nettles.
Dried potato. Whether Smash granules or generic flaked potato, this can help make a soup thicker, add mash to a meal, or be added to flour to make potato cakes (tattie scones).
Noodle flavouring. Either save up little packets from noodles, or some asian supermarkets sell them seperately. I love the mushroom flavour ones, and the wonton flavour (officially prawns are in wontons, but there's nothing non-veggie in the flavouring!) Very concentrated, foil wrapped (waterproof) and you can add to any soup things. Others would suggest cupasoups.
Dried veg/onions/mushrooms. These can be bought in the supermarket. If you want to add them to soups, chuck em in. If you want to cook them for less time, maybe soak them overnight or during the paddle.
Dried fruit. Ace for energy, a little heavier than most other things. A bag of raisins would probably last you a while if you can resist snacking on them.
Sugar and salt. Lots of. Even if you don't use all the sugar, chances are good that someone will run out and you'll have a friend for life if you give them some.
Recipies -
Porridge. Take some dried milk powder, make up with your dried oats and soak overnight in the pot/sealed container - cook briefly in the morning and add seasoning. (For all you crazy types, that'll be sugar. For me, it's salt!
) It'll be marvelously creamy and keep you warm for ages.
Broth. Soak some grains (this'll be a common theme) and boil them up with the dried veg (onions and assorted). Add your boullion and serve with any bread-like item you have. Good for keeping in a flask for a hot mug of when on the move.
Lentil Soup. Again, soak the lentils for a good while and add the dried veg (onion/leek/carrots work well for me). Add a good dod of boullion again and heat on the fire (no need to really really boil hard) for as long as you can stand. Once the lentils are as soft as you like them (maybe half an hour) - eat!
Nettle Soup. There's enough recipies for this, but chances are nettles are everywhere. Grab a (gloved) handful of only the tenderest tops and shred into your pan. Boil up with some boullion and add some powdered potato. If you prefer it a little creamier, mix in some powdered milk.
That's all I can think of right now - as you can see, not terribly original, but possibly tasty, light and reliable.