I adapted an older Tamrac Model 615 for my Super Graphic 4x5. It holds just about everything I need; a dozen film holders, two extra lenses, light meter, filters, and some tools. I can adapt it to a back pack with a set of Tamrac adapter straps.
I have an old Photoflex shoulder bag that has both waistbelt and shoulder strap. It holds a Busch Pressman, two extra lenses, filter, lightmeter and several filmholders.
The best feature is that the top flap folds away from the body when opened making it convenient to work out of bag without ever putting it on the ground. Every thing is right at hand.
On the other hand it is not well balanced like a backpack for hiking.
For hikes where making distance is not important, but instead I am photograping the whole hike, then I prefer to keep the camera on the tripod and use a shoulder bag for the holders and meter.. It can be nice not having to set anything down on the ground. I do this with 4x5 and 5x7. 8x10 is too big.
I will put the darkcloth over the camera, then a waterproof stuff sack -- protects the camera against branches, etc.