Plugin "On site notifications" is very good. But it would be even better if the site administrator could send a notification to all users. You got it?
The administrator sends all users a new notification with a title and a link.
You can develop with individual notification also prefer. So the administrator can use to manually tell the user that he was punished losing points or earned points for prizes.
I would like mainly to send a news site for all other users, promoting a blog.