I quickly added real data to the visualisation so now what you see actually means something. Every circle represents 20 persons either older or younger then 20 living in muide-meulestede-afrikalaan, a district in Ghent, Belgium.
Then I made a toggle button to make kids take up more space. Also in areas with less open space an extra factor will make them even bigger. The results seem readable to me and the toggle makes it easy to compare between not taking additional parameters (open space &demographics) into account and taking the extra info into account.
But who am I to decide over the importance of kids and open space… let’s add sliders.
The sliders let the user decide which parameters are important and get immediate feedback. neat!
code at github.