Below are miscellaneous links that may be useful to other researchers.
VeRoViz: The University at Buffalo's Optimator Lab maintains this open-source Python suite for vehicle routing research. Among many other uses, VeRoViz is great for quickly generating TSP instances on real-world road networks in conjunction with openrouteservice.
Population Estimation Service: If you need a good estimate of the population within a particular polygonal region, Columbia University and NASA provide the Population Estimation Service built on their Gridded Population of the World (GPW) collection.