I finally broke down and ordered some GOOSEFEET down booties with an optional 50% overfill. These are for sleeping. For anything beyond the tent I needed the GOOSEFEET bootie covers which I also ordered.
Since I keep my boot liners in the foot of my -20 F. mummy in winter I did not want down booties with a rand and stiff insole for walking around. Just too crowded in the foot of my bag to wear those. The combination of soft sole sleep booties and over booties is to me the best of both worlds.
As far as I know GOOSEFEET is the only business offering these light over booties. I got the lightest version.

