As far as i know when you are making a scenario you can only make one nation the sole controller of a country.
I would like the ability to make anyone the controller of any of the cities.
Also i would like to make it possible that certain cities in a country can be neutral as well.
The reason for this is to not unbalance the map by making cities independent countries which causes capitals to become less and less important.
a good example would be my current Roman map I am making, in a second Punic war setting.