>>2092228It really is hard to say. It all depends on your volume needs.
In a perfect world you could get all the gear together and then go somewhere to actually test the volume against packs.
Maybe fill the 85L with everything you think you will need and then see how much volume is left. Subtract the leftover volume and see what pack fits in that size.
Owning a variety of packs may be your best bet and then sell whatever you don't use throughout the year. You may eat some cost but as you probably know there is a trial /error cost if you can not get to a proper outfitter to try things out.
I've blown 300-500 testing various sleeping pads, packs, clothing etc. But it let's you dial things in. Plus I have extra shit for guests and backups. Idk about other anons but I usually bring a pack worth of extra stuff and leave it my vehicle.
My overall advice on packs is get lightweight and slightly bigger than needed. I fucking hate packs that are already heavy with nothing in them.