Shah, I don't know how I missed this, but I only now came across your question to me! Sorry!
I did take my Nikon D70s and the 18-200mm lens. It was heavy and sometimes I wished for something lighter, but as a semi-professional photographer I never regretted once taking it. It just has the control I need and the instant on convenience (which allowed me to get images the moment they happened) and the through-the-lens immediacy of viewing a scene (usually I dislike holding the camera away from my face to view the monitor, though sometimes that is just the thing for macro shots).
I protected the camera with a waterproof MontBell camera cover that you wrap around the camera and carry attached to the camera strap at all times. It can instantly be opened when the camera is needed. This cover also helped to protect the camera when I put the camera in my backpack. Not much cushioning, but enough to prevent scratches. I was able to walk in the rain with this setup and not worry about the camera getting wet.
I looked around everywhere for a waistbelt camera bag big enough for an SLR camera and a medium length lens, but everything I found stuck out too much from my abdomen and got in the way of walking and the backpack hipbelt. I just happened to come across the MontBell Trail Lumbar Pack 6.5, which is just a regular lumbar pack, but big enough for both the camera and the lens, plus extra camera accessories like the remote control, extra batteries and flash cards, cleaning fluid and cloth (plus some extra space for my passport and travel documents). I stuck in a closed cell padding to protect the camera and pack walls. What is great about this pack for photography is that it cinches around my waist very snugly and unobtrusively and has a profile that doesn't get in the way of climbing. Also the zipper opening on top opens wide enough that stuffing in and pulling out the camera is smooth and hassle free, unlike any other regular lumbar pack I've used. It is the camera bag I use all the time now when I'm only carrying one lens.
Hope that was of some help. BY the way, are you still hanging out here? Haven't seen you post in quite a while!