Updated first post with v1.04. This change adds +2 Earth gems to your income, the faction now has a total gem income of +6 (or +7 if you took the Sacred Skulls as a pretender). This is now inline with what vanilla nations in Early Age get.
Sorry for all the updates after I said the mod was finished
But, luckily you can update the mod and the changes take effect in your game, you don't have to start a new one (something I wish I learned a bit earlier, lol).