why?
All time restraints do is punish people with bad rng.
All implementing it will do is prolong time in EA at level 4
Another drawback would be the restictive vision of characters without dark vision.
Think of it as a real time cycle and when you go to camp you just kick around there until it's night.
It really isn't a biggy and FAR from needed.
Restreints ? Where ?
EA at level 4 ? Go play something else.
Vision of characters could stay the same, it would not be more ridiculous than behing better hidden when you're under the shadow of a tree...
But it could also become better.
Some spells mostly useless could finally become really usefull, some items could give darkvision, torches, candles, interractive items could really become a part of the gameplay...
Light could really become a mechanic and even if it's not, the world would be more believable.