I'm very familiar with New York City. I was born there and lived there for most of my life. NY is very large
But what matters is the population density at any particular place. The population density in NYC at 14th Street and 5th Avenue is not much more than the density in Philadelphia at 19th and Market. The key data is, on average, how many people will be in any likely bullet path before the bullet is stopped by the wall of a building (a brick wall or a thick glass wall will both stop a bullet from traveling further).
I thought Ft. Lauderdale was the sixth burrough of New York City (at least it seemed like that when I lived there).
-PJ