I would like to suggest an in-game safe method to shutdown the server, my ideas for the command follows:
@shutdown <time in minutes>
so an admin would use for example @shutdown 5
then there will start a broadcast every 1 minute telling "Server is going down in X minutes, we will come back soon." and then it would kick all players then save them and finally close map,login and char servers.
don't flame telling that it is possible to make it manually via X or Y way, my suggestion is that, if you don't like just leave since i'm not going to argue with anyone xd