I know I am late to the party but if you haven't gotten it yet, the Barneys freighter frame is unbeatable with heavy akward loads. When I am not carrying it with the barneys bag I keep a good length of P-cord wrapped between the sidebars at about neck height so I wont bump my head on it. When I need to lash something on I just pull a section and strap it down with that. Its not nearly as clean and handy as using cam straps like a lot of people do but its cheap, light weight, and the P-cord has a lot more utility in other situations.
The Barneys bags are mighty handy too, but they are pretty huge and bulky. Down here in NM I can go back country for as long as I need to with about 4000 cu inches of pack. I think the smallest pack barneys sells is like 6500. But throw a few contractor trash bags in and you can an elk shoulder and hind quarter right in the body of the bag, cinch down on integrated straps and go, much easier and faster than lashing them to the frame.