Hi chaps!
In fact, the night issue depends of the approach you have to AH: if you consider it a game, it has no purpose at all. If you look at it as one of the best WW2 combat simulators available, it should be mandatory.
A day has 24 hours. There should be night for, at least, 90 minutes, every 22 and 1/2 hours of server time. But, to avoid certain time zones - yes, not all of us live in the US - it should be done in a way that it would not hit the same time zones every day...Make it scheduled to show up 1 1/2 hour earlier every day, at a different moment in all arenas.
And, also, make it impossible to tweak on gamma settings. Night vision techniques in 1944 were quite rudimentary...
My € 0,02.