I see two different outcomes through the premise.

1. Set plot-driven episodes where although different players may be intergrated we have core positions who follows every episode. This would place the burden of responsibility more towards the gm/gm's.

2. A The Wire-esque fictional or actual city, where the plot by moderation ofcourse is up to the players, which would place alot more responsibility on the players.

My thoughts are that is difficult to chose one or the other before we would know the number and intension of people who would be interested in any of the two.