Usage of raster maps instead of vector one for low zoom levels.
It may be good to have optional configurable option of a using of a raster map of choice
instead of a vector maps for low zoom levels.
"Use <rasterMapOfChoice(bestIfCached)> instead of VectorMaps if zoom <= <ZoomLimitForRastermap>"
Like using cached OpenTopoMaps at zoom <=8
It may provide some map overview even for regions not covered by offline vector maps and speed up the rendering for low zooms, where usage of advantage of vector maps is slow, compared to low rendered details.