Set default radius to 50 miles... unless...?

[alan-fang]

Is your feature request related to a problem? Please describe.
Angela wants us to set the default radius to 50 miles in our map (I think currently we set it to 500!). Alternatively, we can add a map toggle / additional filter to dynamically set this default radius from the frontend or play around with a similar feature.

Describe the solution you'd like
tbd

Additional context
Add details, any other context or screenshots about the feature request here.

[josh-byster]

I like this a lot. Maybe @eckels if you get the chance it would be great if we could see how and where this would fit in from a design perspective.