Night time

[bardiya]

That would be awesome if you add night time in game ,at the first you may just make object's in game dark and put some light's , but later you can add Monster that only come out at night and new quest must be done at night ,shop's open in certain time and many new situations...

[Arashiko]

Serious code rewriting there, especially for dark and lit areas, and moveable light sources (lantern/torch/wand/staff).

The games I have played that did it have done it from the outset, because it's a significant change.