Ok, so let's say don't touch to the existing ones.
Let's say the only possibility would be to create and destroy new ones.
You have to understand that the conditions to build (and destroy) a city will have to be a very long process.
For example, it will begin with a tent, than a bigger tent, than 3 tents in a same area, than some very basic buildings and so on.
When a sufficient size is reached some NPC will appear...
Conditions to destroy or find such places would have to be thought of and tested carefully too.
As for the "dynamic object", as far as I understood, it's not linked to the object itself, it's linked to the program.
I mean those future little towns would be made of existing models => Kind of a classic tent that can evolve.