I'm kind of excited about this, I hope it turns out fun for everyone. I for one will need to know what scale to use and how big to start pixel wise for resolution, etc.
I think I'm a competing slum-lord with Xyll (You know, we could have titles/awards for this stuff; from Gardeners to Lords)
Does Port Magalie have any landmark places of interest that need mapped out or will you just use whatever gets created? We don't have to necessarily create every building in the city. I can see someone getting skilled at statues or fountain areas for instance. Thus, when creating city plots it would be good to make notes of any significant areas such as town squares or meeting halls.
If someone wanted to create a random house that would be fine but if we need to simplify the project, we could begin with significant places. This falls under the Planning and Zoning commissioner of the city or whoever is role playing the ruling class. Maybe we can have noobs like myself build a few shacks to breath a little random life into the town while the more experienced among us take on the points of interest?