Need Some Input: Characters Interacting (Patreon)

So, this is in no way a guarantee of anything. I just want to gather people's thoughts.
I've gotten consistent requests over the lifespan of development asking for citizens to be able to interact with each other and co-habitate apartments. I'm not against this idea. But I'd really want to make sure it'd be worth the work I'd have to put in for it, if it's even feasible.
What sort of things would you actually want to do if characters were able to interact and live with each other? What gameplay elements would you want implemented?
Again, this is in no way a guarantee that co-habitation is coming. I just want to get an idea of what people would actually be expecting if it were to be a reality.