Looks very slick, but it's really uninteresting seeing where the Rolling Stones toured like that. It doesn't really add anything of any value to me.
Pretty neat. A suggestion: instead of having straight white lines connecting the nodes (cities), why not add color that will change (say from blue to red), parameterizing time, so the trajectory is clear. Also it could be more visually pleasing to "smooth out the kinks", e.g. use splines. Other than well done!
Yes. We tried smooth vertex and personally I thought they look better, but well, got into a design discussion and I lost. The color idea I think is a good idea, also maybe arrows? maybe too old school.