In my case, I try to take clothing with me that can be worn for day and night. I work on the principle of taking two items, one to wear and one to clean and then dry. My routine is to use my time when I camp for the night to change all of my next to the skin clothes and they become the clothes I will sleep in that night and walk in the following day. To keep ahead of it all I also use my tent pitching time to wash what I need to, underwear, base layer and socks mainly. It's not all plain sailing though, my routine can be disrupted by rain, but with a bit of planning I soon catch up again.
In the colder months, I too just wear a pair of long johns under my walking trousers, cause me no problems and when not in use they roll up very small.
I do use my down sleeping quilt all of the time but I am very careful to keep it dry. I had a Rab down jacket recently gifted to me by my son and daughter in law even though I felt that I didn't really need it. I have to admit though that it has fitted in well with the rest of my gear. I've been bothered for a while that my quilt is not as effective as it once was so instead of thinking of taking a blanket to cover me, etc I find that just wearing a clean baselayer and the Rab jacket at night inside my quilt is all that I really need to do. The jacket is also lightweight and crushable and fits into its own small bag which is easy to stuff into my rucksack when not in use. I don't use it when I'm actually walking.