Hi Andy, native peoples have the solution, it's called a tumpline, a padded piece of rope or leather that goes from the pack up over the forehead. Distributes some of the weight to he neck muscles.
Sherpas in Nepal use them to truck their heavy loads. Native Americans used tumpline to carry their packs. Modern day canoeists have tumplines on their packs for the same reason.
Check it out.
Very good Hoz, I did not know the name for this system. I have many pictures of this, one guy in Guatemala has a pack of wood the size of two fridges.
Here in East Africa we have different ways of carrying loads. The kikuyu women use a similar method like that mentioned above which distributes weight to the head and neck muscles and the weight is at the back. Surprisingly it doesnt affect the back. I am always surprised at the load must African safari back packers carry some of the stuff is not even used.
Good thinking! For some years I have been searching for . . wanting to make a bag like the old monks use to carry around in east Asia which are essentially a bag in the front and a slightly larger back in the back attachted to a harness. To date, I have only found these bags on stone statues hahaha.
Looking good, getting excited about this backpack you are chasing,