I have a different approach so will throw that out for thought.
My favorite bags have wheels... I've defaulted to backpacks (primarily the ones with wheels), though I do have one without for the lightweight go anywhere setup. Wheels eliminate the carrying and the strap issue and as far as straps I've always liked the backpack mode rather than single strap over the shoulder for anything (not just gear).
Within those I use smaller bags for the components (a cable and accessory bag), a tiny bag for the M-10 and immediate accessories (batts, adapters, cards), bags/cases for the mics. I don't use a giant preamp or recorder and don't do mud fests (anymore) so it is easier on that front, but I often bring video (all of which is in another small bag) and photo stuff too. I have a Swarovski binocular case (very hard shell - aluminum) for the R-44 and a DVD battery or two. The bags/cases basically fit together within the backpacks (which is easier with lots of smaller stuff than really large components).
With the light rig packed tight I can bring audio, video, a collapsible stand (everything I need) in one small backpack. I've really come to like the folding stand in the backpack as a solution to the urban schlep/crowded subway travel.
Essentially everything with all rigs can go as one medium rolling backpack with the small backpack on my back. The rub there are the stands/tripods which I carry together in one of those big Ikea shopping bags (along with some electrical extension cords). I can still carry all of that anywhere as a single trip (though the stands become burdensome on long distances). I think I need a little better solution for the stands (probably some other sort of wheeled thing that will work for those). One of those bag lady shopping carts might hold everything. For the fest I have one of those folding red fabric wagons which also accommodates some folding seats and cooler.