All night currently does is make it dark.. hard to see.. and even the is useless because of the big neon red tags. It isnt immersive, it isnt fun, it's just plain gamey.
The night is a good concept, perpetual day would get rather boring. But, there are no perks to night other than giving the odd low-level lanc carpet bombing better survivability.
HTC already modeled some really nice lighting effects (Cockpit lights.. (the combat trim ones, gear, etc..) from fire if you pull next to it during the night)
You could get rid of it, which would be a better short term solution with AH2 in the works, simple as changing the morning and evening settings.
After AH2 comes out, however, it would be a good idea to fix it.
Some of my suggestions are.. Add some spotlights on the fields, possible from the ack guns, that follow that ack's target. (Only a few should have lights..)
More (hell, if we have any now) field lighting, hangar lights, lightposts, etc..
Landing lights!
Possibly for TOD and scenario use..
If the radar is disabled or changed, we could use the radar on radar-equipped night fighters and bombers. (Mossy, 110, etc..) that would illuminate a set radius, of if possible, be effected by hills and mountains. It could also increase tag range, or if no tags are used, have them appear.. Maybe 1 perk for use, or maybe none, since not everyone is gonna wanna be flying a Mossie for it's radar..
[Edit] Nononoooooo, what was i thinking? not illuminate, give dot dar coverage to an area smaller than that of a field dar but not -too- smal.