Many games have default or archetypal settings. Seattle, for Shadowrun, is a perfect example. GiTO has NYC. In many ways, NYC typifies the entire game, as nearly any type of adventure the setting supports can be found here.
The core is a typical Enclave, high tech, happy, clean. (Well, “happy” if you’re a resident. Not so much otherwise.) There are many adventures possible here, from bank jobs to data runs, assassination or bounty hunter missions, body guarding or monster hunting, con jobs and political smear jobs.
The jungle is an urban nightmare. It has very different opportunities: gang warfare (against a gang or for a gang), lawmen-for-hire, raiding a company compound, guarding (or raiding) a convoy. Then there’s assassination or bounty hunter jobs, body guarding or monster hunting, and so forth.
The wild is largely empty of human life. Still, lone nuts and small settlements can be found here. It’s also filled with nests and lairs of strange and monstrous creatures that emerged from the vortexes. Also common are tribes of Beyonders who fled the dark forces consuming their world.
Then there’s the tunnels, an entire setting in and of itself, complete with settlers, survivors, and monstrous beasts.
And the vortexes.
Vortexes are not a rare thing. Many Guns find employ fighting the creatures that pour from a newly opened vortex; many find wealth venturing into the Beyond (a very different adventuring opportunity).
So, in the same city you can go from a high tech city, to a crime ridden slum, to a gang-ruled urban hellhole, to abandoned zones where monsters thrive. Nearly any adventure opportunity the game offers can be found somewhere in NYC.