Per-calendar styling

I love the device calendar feature, and seeing my events at a glance in the month view gives me a fantastic overview of upcoming events. However, aside from my personal calendar, I'm also tracking two other calendars, and it's not always immediately obvious which calendar each event belongs to. I would be so happy if different calendars could be color coded to show up with different colors in the journal. Stretch goal: allow the user to select a custom icon for each calendar - i.e. a "person" icon for the personal calendar, an office building for a work calendar, a family icon for a shared family calendar, or similar.