I'm in a fairly similar place winter gear wise, I prefer to have a roll up foam mat (150g) in addition to an inflatable. Handy tip: for cooking, especially mid day, sit down and put your foam mat on edge around you and your stove, makes a nice big windshield

I carry a lot more insulation clothing and a lighter sleeping bag though. PHD yukon and minimus trousers. Those combined with a neutrino 400 in a bivvy and I'm toasty, makes getting out of the bag easy too

I have a lot of things set up so that I can use them in summer and then combine with something else for winter.
I'm actually getting heavier though, 1.4kg of camera gear at the last weigh in, but when everything else is so light it's fine.
I've got my summer gear for a weekend down to fitting in a 20l pack, with just shelter(hammock+tarp or Trailstar+bivvy) on the outside and chest mounted camera bag. But it's untested. Soon