Workflow: GH adjust indicators in drop down; ‘bake;’ post process in Illustrator. Color. See examples:
You will need Human and Lunchbox Grasshopper plugins
https://lcabcn2014uo.wordpress.com/2014/07/12/smellssounds-of-people_mirandasawyer/
A VERY simple drawing with very lightly drawing 3 x 3 nine eixample blocks AND differentiated LINE circles would be very sufficient.
Happy mapping.