An idea that I raised during a discussion between the language committee and Wikimedia South Africa was to inform chapters when a request for closing a wiki is made for a language that is spoken in a country which has a Wikimedia chapter. For this I made a list on http://meta.wikimedia.org/wiki/Chapters_per_Wikimedia_language -- it took me some time but I think it is well worth it.
So when proposing a wiki for closure, you should inform the main chapter listed there so they have a chance to find interested people who can contribute to the respective project.
The list can also be useful when opening projects. If wanted, I or formally the language committee could also directly inform chapters when a wiki is opened in a language spoken in one or more countries covered by chapters.
Regards, SPQRobin