It's not a huge thing, i just think the AI seems to be omniscient in night time situations which doesn't allow to use stealth at all. most of the time you get spotted before you can even see your enemy although YOU are the one who is looking for them in the first place.

also i have a suggestion: the nightvision is almost a little boring. it would look so much fancier if there was a goggle type that uses a night/thermal-vision hybrid. you know, like in battlefield 3, night vision combined with thermal. just an idea, would make it look way cooler.