More Room
I mentioned pockets right? The M-Rock Zion 525 has them; enough of them to ensure you have room for all your smaller items. Each access panel has pockets on the outside as well as the inside.

The top access panel’s exterior pocket has a key clip, two smaller tension mesh pockets and one large mesh zippered pocket where the Weather Jacket is stored. The larger mesh zippered pocket also has access to the wire port that allows you to pass through headphone wires from a CD or MP3 player. The access panel on the bottom exterior pocket has two large tension mesh pockets and one larger zippered mesh pocket. The large interior zippered mesh pocket stores the fairly handy attached lens cleaning cloth.

The M-Rock Zion 525 has a lot of room to store all your goodies. I was a bit nervous that it would not allow me to carry my tripod, but it seems M-Rock has thought of that too! The elastic web straps on the front of the backpack can hold a tripod securely. Slide the tripod in, put a foot or two into the bottom little zippered pocket and cinch the two elastic webs tight. There is also another elastic web strap on the bottom of the backpack which could be used to carry a jacket. You could also use it to carry your tripod instead of attaching it to the front for easier access to the exterior pockets.
Lots of Customization
There are some common configurations you can create with using the included dividers, though I am sure one can create more possibilities with the amount of interior room there is. I’m impressed that I could fit a full frame dSLR body with a large lens such as a 70-200mm and till have room for a few other lenses, a flash and whatever other devices I may need.

The first configuration is what I currently use. It allows me to keep my kit lens (18-55mm) attached to my Canon XSi (EOS 450D) along with my Sigma 550 EX Flash, my Canon 70-300mm, a Canon 50mm 1.8 in the larger lower compartment. Removing the accessory bag allows for even more room, like a wide-angle zoom. You could also fit a telephoto lens at the very top if you needed to.
Another common configuration allows you to use a dSLR body with a large telephoto lenses (such as a 70-200mm) still attached to the camera body. Though with this configuration you may need to open the bag fully to access your camera. But you can still store a few items around the camera section as well. I am sure people will be able to create other configurations as well with the Velcro, padded dividers. The possibilities seem almost endless depending on what you need to transport.