Inspired from a recent xgame question. I think it would make a lot of sense from an RP and realism stand point to have a day shift / night shift grouping for NPCs. Poor old Rychek works every hour or every day and night at the Drome, I'm sure he'd like some time off to spend that hard earned flash!
This would be kind of a big time sink, creating and assigning NPCs, but it would give the night time and day time a more differentiated feel. At some point, the night owls come out and a changing of the guard takes place.
The shifted NPCs would take the same functional position of their counterpart, so no loss of function there, and then poor Rychek gets to finally leave the Drome and go back to his apartment and sleep, perchance to dream!
This could be extended to all NPCs, given that it is well received, even the gangers need to sleep sometime.