7) Maybe weather effects? On different maps or as different gameplay modes or changing in game? Weather, that changes vision of your units (fog), speed of your units (winter, where some units moves faster, and some wheel-units (or bikes, or something other) moves slower), rain (decreases accuracy of some or all units), storms (disables air or reduces air effectiveness, like air will move slower as exaple), extreme winter (no infantry, or infantry moves slower, or you must move infantry all time, because it will be frozen like in RA3 by Cryocopter and easy killed), extreme storm (1-2 of your vechicles will be taked up