Well it's a You thing the bag must be comfortable and your size but this is a good channel for general advice.
This is what I would use:
The TERRAPLANE is MYSTERY RANCHs most time-tested, expedition pack with a top-loading design, long torpedo pockets, and a detachable lid for ultimate organization, versatility, and load control.
www.mysteryranch.com
Or this:
DALL The Dall is the bigger brother of the Gnargali pack coming in at 7,080ci (116 L) and 6,080ci (99.6 L) with the snow collar used as a lid. Made from 500d Ranger Green cordura and VX21S Coyote Brown Xpac, it has the same water resistance as our Muskeg series. Two belt pouch matrix’s on the...
kifaru.net
I would get a bikini frame with non aluminum stays.
I could give a deep dive on packs but at the end of the day you want the best back FOR YOU
You want it as big and as comfortable as possible to give you the most options.
In fact you should keep some ten pocket pants like some Crye Field Pants and Shirt in the car to properly distribute a load should you have to leave your car.
These packs are insanly expensive but it's a buy it for life thing and you can send them back with no problem because at this level packs have to be sized for you and they make not work for you.
No matter what Pack you get it should be a Hunter's pack or a military one.