tabanli, probably I can't understand. Hope, you will explain your questions for I will be able to answer with more details
As I've undrestood your questions, answers are:
1) Cities have the same defenders as before, nothing's changed.
2) To see units and items is enough to open the map in map editor and look at them. In a game you need to send a unit close to them, then to look at them.
3) Center cities is the same, nothing's changed.
All is changed is that corner cities are now citystates. Also items in high danger ruins and it's defenders are changed, just a little. No more.
Reason of making citystates is that it will be not so easy to take corner cities and others close to them when game is 1x1.
I am glad that you like Battle Field map. The map gives many ways to use any tactic you wish to choose for a game. Hope you will have fun of the map many times.