I try my best to maintain the RP of a crowded city, and I think most of us do, but it's easy for the mind to just see "2 pc and 1 npc in room" and go "yup, there's 4 people here counting me."
I really like the way the current NPCs walk around, go to bars, use the elevators and the levs, and I'm imagining a scenario where we have like 4X as many of them wandering around, could make the city feel a lot more alive.
Could even have it set up so that the gangs/judges occasionally stop them and harass them to show ID or shake them down for their extra flash.