Please modify so you don't have to completely exit the game and restart it to switch servers.
Add an additional button under the "gear" menu to go to other server, or to go back to login screen. Otherwise you have to close the game out and restart it.
Alternately you could add a step like some other games where you go back to the login screen after you exit the server, but seems like that would be well less frequently done so the first option is better to add a button under the gear menu.