The alaskan guide frame works nice w/the shelf folded down. You don't like it?
I also have a set of the "human" panniers from Carltons, but have forgotten to take them with me. They look like a paperboys' rig, but on steroids! I have loaded them up pretty heavy during trial runs.
But like someone else said earlier, if in very far/steep, found that any frame/pack/pannier will handle all you can handle and then some.
My best suggestion.......forget a bigger/nicer pack. Get a bigger/nicer friend to help out!