I would suggest you modify some of your ideas.
The idea of a site in a tarball is great but perhaps it would be better to have a news aggregation site and spyop repository. Use that site to dole out information to the distributed sites.

This means not everyone needs to link to earth newsfeeds and redeploy their sites if something is changed and also would allow better implementation of spyop sharing with little to no changes required to the client distribution.

I would also suggest that you make it modular... Perhaps make your own forums module and then make the earth tools a module, design a basic framework and module manager and make sure you have a strong intelligent API.

This is the old if you build it they will come pattern.

If I was interested in hosting an earth site this is what I would be interested in, perhaps some have different needs.