i only have this issue on snowy mapgen maps, not man-made snowy maps
That's interesting, because the snow biome is made from the settings from Frithen. If other snow maps are okay, then we can do some tweaks to improve the mapgen snow maps. Is white fire okay? Feel free to name some maps that you think look nice and are readable, then I will take a look.
and maps have a brightness slider that can be adjusted very easily.
I thought your laptop has a brightness slider? Did you mean that?