Hill People Gear is now offering HDPE frame sheets that are precut for their pockets like the Pals Pocket, Admin Pocket, and Tara Pocket. It also fits packs like the Tarahumara and upcoming Junction Pack. These sheets are a simple and inexpensive way to make these pockets more comfortable when used as a standalone pack.
The sheets add some stiffness to the pack which helps it hold its shape instead of rounding when stuffed and helps prevent the wearer from feeling odd-shaped cargo pressing through the back of the pack. You can also find other uses for them once you are in camp like a cutting board or a way to keep dry tinder off a wet ground.
I previously used a Tarainsert for the same purpose. It adds a significant amount of organization capability but costs and weighs more. The new HDPE inserts are certainly a simpler, less expensive option.