consider showing more contextual information on summary plots

[sangeetabhatia03]

user can colour by one or more of contextual fields, but could we show some context on the summary plots in a pleasing way?

[sangeetabhatia03]

@patcatgit this is something we were talking about before the London hackathon, but I haven't captured enough details to understand what you had in mind. Could you maybe draw something on a paper and attach it to this issue (if you still remember what you had in mind)