Welcome to the city of Atlanta, Ga.

The first step in city creation is to identify 3 themes or threats in the city.

idea1: Atlanta served as the effective capitol of the Southern US back to the days of slavery and succession and harbors many old hatreds. While in mortals the animosity is receded some, old mind cling to old hatreds. In the city of Atlanta cultural mistrust is elevated. Mortals in the know tend to be less likely to trust anything supernatural, and even the two families of white court vampires can't work together for any length of time.
Theme: You MIGHT be all right, but I don't really trust your kind.

Your history needs a little work.  Capital of the confederacy was Montgomery, Alabama, Richmond, Virginia, and briefly Danville, Virginia.  Atlanta was an important travel hub of railways even then, and certainly a bastion of the South, but to call it a capital in any sense is stretching it.

idea2: Cities tend to rise up in places of power. There used to be a confluence right where the center of the city is now, but it receded a long time ago(several centuries at least). The N-S ley line along 75/85(interstate) has been there all along, but an old ley line running E-W has started to rise up again along I-20 and a confluence is gaining power right smack in the middle of the city. If all that nonsense with highways and ley lines isn't enough, then just for your personal amusement my I introduce 285. 285 is a big freaking circle of a highway around the city. People in the city call it the perimeter. Where you live is described as inside or outside the perimeter. This just has to mean something.
Theme: Rising Power

Circles mean barriers.  Barriers mean containment.  Carry on.

idea3: Someone shot the warden. Right through the back of the head. They got the drop on a guy that grew up the child of slaves. The warden in Atlanta was a bad motha and kept the city power structure in check. Everyone wants to further their agenda, but NOBODY knows who killed the warden. The timing is awfully convenient, with that new confluence and all. The death looks like a simple mugging, but there is NO way a mortal mugger could get to the warden without outside help.
Threat: Power vacuum

Says who?  The dead warden maybe?  Last I checked, Wardens bled just as easy as any mortal, a little easier than many supernatural beasties, and as a rule tend to specialize in fighting monsters and wizards rather than mooks and thugs.  Not saying the premise is bad...just that one unqualified conclusion seems to depend on a large amount of PC genre savvy to get where you want it to go.