Hello,
I thought bout something. Adding day and night cycle to RSC. Why you say? Some NPC could only spawn at night and some during day time (NPC's that would drop hard or epic clues)
NPC that could give points for something special or simply "Unique quests NPC" that could give you quests randomly and some epic rewards.
Thieving could be easier at night and stuff like that.
Possibility is endless.