Sooner or later the dev team will look at creating new maps/worlds to expand the game. May I suggest that these are sequential, in that you move from map "a" to map "b" and then reconnect to a server running that map and vice versa. So, if you make it out of the North of Chernarus, for example, you have access to a whole new map, but if you die then you restart at Chernarus. This would continue the game's idea of story and progression, unlike other FPS'es, where you can just join the server running the map you fancy playing at the time. It would also add the idea of "going somewhere", trying to find a haven safe from the infection. There should be some sort of border, like a range of mountains or a cliff down to the sea, or even a wall or fence, so that the map designer can choose the points at which players may pass between maps and simplify the sign-off between old server and hive, and hive and new server (however it works).