Pictures above provided in response to requests for more info/pictures.
This is one adaptation of the basic frame. Three bundles have been lashed to the frame. This is similar in concept to the Luxurylite packs. I experimented with this about 20 years ago but found that I preferred on big bag instead of three bundles lashed on to the frame.
The frame, shoulder straps and waist belt of the pack pictured here come in at around 12 ounces. It would be easy to shave some weight because the shoulder straps and waist belt aren't very light. I robbed them from some other packs.
This pack can be constructed with no sewing. The shoulder straps and waist belt can be salvaged from 2nd hand stores and almost any stuff sack can be lashed to the frame. Campmor, for example, sells 10" diameter silnylon stuff sacks for $13 that weigh a little over an ounce and have about 1500 cubic inches of capacity each. So three of these could be lashed to the frame and total pack weight would be about 1 lb.
With quick release buckles these three bundles can be added or removed from the frame in seconds.