These are all really great comments!
Undoubtedly each area of the city serves multiple purposes, especially since the Rikti invasions and the meteors and earthquakes and such.
For an MMO experience, obviously there will be mobs and spawns running rampant for leveling up via street fighting. For a table top RPG experience, the world would be much more sedate. I think Croatoa could fit nicely as the "quiet suburb" if you imagine it for the table top.
Independence Port is definitely the commercial district. I was thinking commercial as shopping and Skyway sprang to mind. But I think you are right, Redlynne, that commercial is more in line with shipping and ports and such. Striga too. And to a lesser extent, Talos.
The industrial and generally run-down aspects of Kings Row is why I looked at it as the "bad part of town."
I agree Founder's Falls is a trendy neighborhood, but it feels more upscale to me. Talos is the trendy neighborhood for the common folks
I love the idea of ethnic neighborhoods within the city, and have some good ideas there, Techwright.
If i were to pick three descriptive words to characterize Paragon City with, I'd say bustling, diverse, and sprawling.