I would be curious to discuss more and compare thoughts. What kind of size maps are you doing this for? I am hoping to figure out a good way to make 300km+ maps. Was thinking maybe I would bake out landscape data layers at certain “levels”.
For instance, using a height map where 1 pixel = 1km, using 4k maps (maybe 8k? But was thinking 8k textures are slow to process) and baking the solar data for this (Scaling down the landscape to proportionately to 21km to fit in Float error range etc.; however I think in 5.4 there might b plans to make possible near infinite (very very massive) landscapes and levels; then in areas where I need detail (Cities, places of interest etc.) I would use a scale of something like 1 pixel = 100m and then finally 1px = 1m.
I would then (not sure on math) use the larger data layers as area averages, and then (I guess?) add the next layer to the large average, and then add each layer after that in the same manor.
This way I can get good results that look and feel correct for large areas, as well as small areas where they are needed… The center of each map would have a world location in Long/Lat for positioning when baking and knowing when to load level if that area is rendered.