In a prefect world, your sleep clothing should be a coordinated part of your insulation system and sleep system, available for use whenever needed. I would not carry clothing to be reserved only for sleep.
Depending on the weather, I would normally wear a long sleeve base layer and have a fleece mid-layer and puffy layer for camp. Unless it is full-on hot summer weather I would also have light to medium weight long johns that I would wear under rain gear and/or for sleep. If it is colder than my sleep system can deliver, I would wear everything to stay warm, including rain gear. That is rare.
As far as staying clean, sure, make the effort, but don't be afraid of a little dirt. I take a sponge bath at the end of the day whenever possible. If my base layer top is too sweaty, I can always wear my fleece mid layer for sleep. I do carry spare socks and would wear the driest, cleanest pair for sleep, or both if really cold. I wouldn't be adverse to wearing gloves and hat as well.