I have always used a wet and dry clothing system…
wet is what you wear during the day… as soon as I have set up camp I change into the 'dry'- generally something like a 164g long sleeve top and 190g wool long johns… if it is cold I wear more insulation…
I wear the base layer in the bag with liner socks and maybe a light beanie. The advantages are you keep the bag clean, you feel better not having the skin on skin thing going when sleeping, you can wear this stuff if needed as more baselayer, but the big one is just a the change of clothing around camp – very civilized…

