IMO, I don't think Harns should be sleeping when time still isn't even implemented yet. I mean, we have no dating system, no calendar, and the IG time restarts whenever there's crash. Currently, the only effect IG time has (other than lighting) is making Harns inconveniently go to sleep (or at least that I've seen so far).
Once a dating system is put in and time actually becomes a factor, then I'd like to see this implemented, and with all NPCs.