I like the idea of starving a continent of new characters: maybe say no new characters on some continent. Just drop it from the whole character creation process. The characters there would slowly dwindle until it was a Mad Max-esque wasteland of lost hopes and dead realms. And the RPs that could be done about the end of society, etc... monster/undead problems would grow and grow....
And eventually, when it got too small, we could close it. Alternatively, if we get a player bump, we could re-open it. This allows us time to consider what to do. ALSO, it makes that island unique for its last time in the game: and I could see that island being VERY popular if it was re-opened. i.e. like early Dwilight and Beluaterra after invasions, the colonization craze would kick in if we ever re-opened it.
Note: I have not read the whole thread, so if this was proposed and rejected, I apologize.
