I took a quick look at the viz and I did a few things:
1. Change the Mark type to Circle
2. Select the Size Shelf on the marks card and slide it way down
3. Right-click in the pane and select show trend lines
4. right-click on the trend line and select edit, deselect Show Confidence Bands
5. Create a duplicate of the view and add District to the rows shelf--this creates small multiples views that are easier to parse.
6. Add the view to the dashboard.
I'd love to hear your thoughts about how this does or does not meet your needs.
Thanks for this Nicholas, very helpful.