As John stated, there is no clear answer. For me, it is what will make me comfortable while minimizing weight. My packing is usually a result of what happened on a previous trip. For that reason I generally take too may tubes (five) because on one trip I ran out of tubes (I had two) and found myself in a land of mountain bike tubes, but no road bike tubes (I ride 28's on tour). Like John, I will take a fiberfix, and I will also have two extra spokes. I have the necessary tools to tighten nuts and adjust cables and brakes. I have a spoke tightening tool. I do not take a cassette removal tool. I have a small container of extra nuts and bolts. I take a small amount of duct tape. I have two zip ties. I have two flat repair kits (again, overkill, but there is always a story). I do not take new cables, but I do ensure that all cables are in great shape before I begin a tour. I take extra brake pads (four). I replace my tires with new tires before the start of any lengthy tour so I do not carry a foldable spare. I have an emergency Park Tool tire boot. I take an extra battery for my cycle computer. I have a small bottle of Dumonde Tech (lite) lube. I have a chain removal tool and extra links. I am sure there may be one or two items that I carry that I am unable to recall, but as I stated earlier, some of what I carry is based on something that happened on a tour and I vowed, not again. Different strokes.