[PvK]

Very nice! I like the discussion and related ideas, too. It is very interesting the idea of pretenders who can generate units (especially with abilities a nation might lack without that pretender choice, such as inquisitors) and I like the idea of an immobile building that could generate the head-of-state too, except that'd probably require the player to self-limit himself from summoning many (unless you can take the unique unit ability from some unique existing unit or something).

I agree that the immortality can be explained by choosing the replacement based on his "stigmata" by people who believe he is a vessel for a holy spirit, that the story of each incarnation is significant, etc. Also if he dies outside dominion the Call God period can be construed as there were insufficient witnesses who are trusted enough in the faith that the old Ecclesiarch has truly fallen, or the details of the story haven't been confirmed speedily and consistently enough yet so there are still arguments about who should replace him, etc.