We do the hike-setup-hike scenario nearly every trip, lately, since the sites in RMNP are reserved and there are so many cool alpine lakes, so I have bought packs that were meant to compress a lot when not carrying the whole kit.

For about 15 years, I used a Golite Jam pack which has clips at the bottom and long compression straps to shrink the pack. Now, I carry a SD Flex Capacitor which compresses horizontally down to 25L.

I have a little daypack that is designed to flip inside out to be a stuff sack inside a larger pack, but haven't used it like that.