This is a terrific project, thank you!

Use-cases will vary widely. For example if I used Brolly for sailing, I'd want wind speed in kts and wind direction as well as dew point, and I'd want a recent timeseries of air pressure to give an idea of the synoptic-scale situation.

Of course these may be far outside your original use-cases. I think when people get a hold of Brolly, they're going to love it immediately, and there will be a flood of feature requests. If that happens, might be good to design the layers needed for diverse customization.