My third, fourth and fifth cities will be resource cities, with equal amounts of wood/stone/iron and food (use the auto city planner to maximize resource production)
My actual cities on world 83:
Third city: http://bit.ly/VNrqVQ
Fourth city: http://bit.ly/ZDzEpb
Fifth city: http://bit.ly/VNrIfo
My sixth city will be a full zerk castle. This city makes 3 sec zerks and has a max capacity of 300k troop strength (TS). See http://lordofultimastrategies.blogspot.com/2011/09/how-to-build-kick-ass-berserker-castle.html. This castle recruits zerks, and my second city will not switch to recruiting rangers.
Now I have 2 castles, my second and my sixth cities. When I have enough purified resources to research my second city, I will get my 8th city for free.
My 7th city will be another resource city and my 8th will be a castle. When I have around 10 cities, I will go full military This means I will stop building resource cities, unless I take a lawless that's a resource city. Most of my cities will be military. I castle both offensive and defensive. They are always raiding, even the defensive once. Raiding brings in about 4 -10 times more than a typical resource city, so in the long run you will grow faster with raiding cities. I will also build food cities and hubs. Zerks are the best for raiding, but I also build Knights and Mages for war. For defense, I build rangers, pallies and xbows. Navy comes later.
My 10th city is a regional hub with baron launching capabilities. This will allow me to launch 5 barons at once.