[Endoperez]

While that is an interesting suggestion, it's way more complicated than what can be done. Basically, we can only do stuff that's similar to what is already there. The Keep of the Annals can allow recruitment on units/commanders, produce X gems/gold/resources, affect scales etc. The features are also limited to four: the Keep could allow recruitment of sages, knights, produce 3 astral gems and increase magic scale, but not have a fifth feature.

There is a property for scrying distant provinces (EA Agartha's starting site has this), but it can't be added to custom sites.