Well looks like you know what you are doing and you do not need any suggestions so I hope you will not be offended.
Personally I would lock the page after minute or two with pop up window that will only allow people to continue use after joining (facebook page, app, twitter, email). Especially joining with app able to force share likes might make this go viral like rocket. Well again, according to your join date and number of posts you know how to play this game
)