From what I remember, not seeing opponent that is attacking you, gives them 100% chance to hit in meele, high stance with shield removes ~half of our eyesight for protection against projectiles. My questions are - how ranged combat vs eyes work in this case, only possible hits to eyes are blocked where our sight is blocked or protection is bigger? And how meele will work? Will enemies hit me 100% of the time there?
Also I remember celling counts as outdoors, and I vaguely recall one of updates changing how temperature work a lot, does my cabin need to be 100% hole free which excludes having cellar inside? I remember that wild animals will steal food, so I could make at least one additional room for cellings so only robbers would be birds.
Cellar inside can be done without a problem. Even with current upgrade, you can survive sleeping on the inside cellar during winter if you have warm clothing, though snow will still wake you up. I make my cellar just a few metres off my sleeping space, which is near fire. It has no effect on perceived temperature - my character still sweats a lot. This cellar is very convenient, when you stand on it, you can prepare dried food (there needs to be a wall nearby, may be diagonal), which you don't need to care about moving to the cellar when it's done.
This can be still robbed by non-avians, assuming you let you door open.
I fight with the shield often, and enemies definitely don't have 100% hit chance. The melee fighters with axe will devastate the shield quickly, though. One hit can even lower quality by more than one level. Also, even with the anti-arrow stance, the arrow can sometimes hit you, including in the eyes. Still, it will block most arrows coming from front. By the way, when melee fighting with shield and HIGH stance, you can still be hit by your melee opponent in the eye, too.
Enemies seem to have some advantage when attacking off sight, and if in group, some of them will try to flank you. But my character is so armoured, than these attacks rarely are very dangerous.