I played several "night missions" and my impression was that there was to much light. When I was playing X-COM, the maps were almost black during the night, and flares were essential, as the aliens could see better in the dark. Besides, those kind of missions were the creepiest of all (I remember best the farm and the jungle missions)
Right now, the night time missions are under a full Moon or two, and there isn't much use for a flare. I'm also suggesting a flare gun, that launches flares like the grenade launcher
