Dan, the short answer is that there is no ideal system. You know that!
Yeah, I think I do know that. I was just hoping that someone, somewhere had come up with something better.
I have a decent system worked out for day hikes, where I use a Mountainsmith Lumbar pack for much of the gear, hang the camera over one shoulder and around my neck, and hang the tripod back over the other shoulder. I look like some kind of freak, but I can get to everything without too much fuss - and easily drop the lumbar pack to the ground when necessary.
On the main packs shoulder strap is a pocket (ala Colin Fletcher) which holds a Olympus Stylus or similar just in case Bigfoot strides across the trail.
That is an interesting comment on two counts. First, you know about Colin Fletcher... ;-) I've been a Fletcher fan since I read Thousand Mile Summer, well, a long time ago. Many bits of his wisdom have stuck with me for many years.
Second, I had not though of carrying a small point and shoot camera in an accessible place. There are some now that are good enough to be useful for certain kinds of shots, like those of my hiking partners smiling at the top of some pass.
When a serious picture presents itself I remove the backpack, setup the gear, then evreything goes back inside again. It is a pain but I cannot function anyway with the loaded backpack on my shoulders while I take a photo which may be a landscape or a mushroom.
I've found that I can manage to set up gear with the pack on in some situations - particularly those that lie somewhere between "point and shoot" and "spend 15 minutes getting it just right." For these opportunities I'd love to come up with a more efficient way of packing the gear, especially the tripod. That seems to be the major complexity.
Somewhere, someday, someone is probably going to come up with an imaginative design for some sort of tripod holder that attaches to the pack on the side and is canted forward such that one can get the tripod in and out of it with the pack on.
For now I guess I'll continue to get along with the tripod attached to the back of the pack.
(Who appreciates your nice words about my web site. Where do you tend to backpack? I'm a Sierra Nevada guy myself.)