I like to imagine that city building games are already first-person; just that the person in question is an invisible floating omnipotent sky-mayor. A mod for Cities: Skylines offers the more traditional first-person view—albeit one from what appears to be an improbably tall citizen.
The mod allows you to explore the streets of your city. It's a simple camera switch, but one that offers an interesting perspective on your city's simulated citizens. It would have certainly let Chris L get down-close-and-personal to the occupants of his single-house city (opens in new tab).
Below you can see the mod in action. If you want to try it out, head over to the Steam Workshop.