Types of maps

In video games their are many types of maps the biggest two are open and controlled.  Open world allows you to move freely around a map and you can do a lot the best example is Elder Scrolls.  I like this type of map because it is always fun to go somewhere different every time.  Controlled maps allows you to see a lot but you can not go to though areas.  Some games do this well like Dragon Age but that is squad type fighting.  Maybe that is something to think about too, most squad type video games have controlled maps and most single player have open.  What do you all think?  How should I think about my maps for this game?  Any input will be welcomed.