Seilore,
Recently (1.6 or 1.61 I don't recall which) improved memory usage in a way that would be most noticeable on "extreme" maps. This improvement would only apply to newly created games. Other than that, we haven't done any W10 specific optimizations.
EDIT: the memory fix was related to number of factions, not map size. So a medium map with lots of factions would see a benefit as well.