I'm not sure if you are already planning this, or if someone has already suggested it, but I have a couple things I thought would be nice if they were configurable.
- Setting hypo/hyperthermia: right now in my survival world, I've got hyperthermia in the middle of a summer night. That's... kind of silly. It would be nice if we could raise or lower the temperature at which hyper/hypothermia sets in.
- Configuring water stored in bottles/canteens: at least in the early game, it feels a little unrealistic that you only get three gulps of water from a canteen, and you need to maintain access to water or else risk dehydration.