This is a really great idea to stop the "sink and pass" issue that plagues many servers. It won't stop it but will def discourage it. You get four sails so give four (possible) sinks; the game now gives you 3 maps while completing the assistant; and you also have the chance of getting a map from guild chest. So that's at least 5-7 maps- more than enough. I hope this idea gets some consideration.