My current thoughts, based on your suggestions in part:


Towel: super absorbent and compact

Clothes: ultra thin wicking poly/merino wool:
socks
pant, preferable footed or stirrup
top, preferably hooded

insulation layer, high tech and thin:
top to toe as above

ultralight hooded rainsuit

ddry footwear ?water socks?

Insulation from more cold
bivy heatsheet
ultra light ground pad?

Hot liquids
?self-heating soup

Multiple hot packs to "wear"
armpits, groin, back of head?

Easy to eat and absorb energy food
self-heating stew
chocolate ?

Wetfire tinder and stove

Sparkie one-handed blast match

Water:
Nalgene bottle "wearing" a TI cup

Can "wear" the bivy at need as an outer layer

Maybe the size of 2 breadboxes?

In a dry bag inside the smallest workable daypack?