We work in European cities. If you want to see how different it can be from US or Asian cities, google "Nantes" and see images.
have people, the final users of the service of general interest represented. it can be by a feet trace, or by symbolising the outline of people see
http://pdu.stif.info/ (the horizon line in different colors) or
http://www.blog-ethicity.net/ or
http://www.ecopole.com/
comment on the first two choices f style sliders : it is feminine as there is a sense of deduction, a sense of seing what needs to be fixed, and masculine, as the work has to be very rational (reports on field surveys); it has to be simple as we want our customer to understand that we have a clear view on the reality, and complex, as we report the situation as it is in a city with eg 300.000 people having a diffrent experience every day ! (organic or fractal logo can be a possibility, like having fern, which can represent the complexity of the system in each single part of it);