• Synoptic charts -> E.G. GpH 500 Hpa & Temp 850 Hpa
• Snow

Preferred is maybe 1 file or location to alter these predefined maps, so that people can submit merge requests easily.

My suggestion:

• New url structure for raster, contour, arrow as arrays[]: &raster=temperature_850hpa,&contour=,geopotential_height_500hpa

Which allows fully customisable layers