Panniers lower the center of gravity and make the bike much easier to handle. I toured with front and rear panniers and rear rack-no handlebar bag. I liked not wearing a pack-just a fanny pack. Much easier on my back. I put my sleeping bag, folded up pack, pad and tent on the rear rack. Everything else was in the four bags-clothes, boots, stove, food, misc. stuff, and bike spares and tools. I carried a spare tire (folding Specialized), tube, spare cables, pump, and tool kit.

The front panniers should be centered on the axles-I don't think all of racks do that. Mine were Blackburn, I think.

My bike, fully loaded weighed about 80 lbs-30-35 for the bike and the rest bike and hiking gear. I lowered that considerably by shipping unneeded gear between towns by bus and picking up my stuff when I got there.