Teine--
My current approach for securing (tape) wicking is to drill a hole through the shaft of the staff, pass a machine screw through the wicking, into the hole, and out the wicking on the other side. Fasten a screw-post (sort of an elongated nut) on the other side, using heat-resistant loctite. Washers at each end, but you don't need washers between the wicking and the shaft, and you don't need very large washers on the outside, either. I do have a layer of copper foil over the shaft (I use wooden shafts) for fireproofing.
Melissa--
My concern with rope wicking is that if it developed some slack (which could happen over time), it could be jarred loose and would come uncoiled and fly loose except where it was anchored. This would take some experimenting. Eating/trailing torches are not generally subject to the same stresses that a staff is...I don't think. So they don't need such care in attaching the wicking.
The idea of a hollow staff filled with rope wicking is very intriguing. You might not get all the wicking soaked, or if you did, the fuel might not all wick out before the fire petered out, but it's still an interesting idea. You could have the overhang coiled around the ends of the staff for the visible wick and pinned down somehow.
For kevlar twine, I'd check at McMaster-Carr (www.mcmaster.com) if you're in the USA.