Well there is no URV, so the third UHV could be to reestablish the Pentarchy by having an Orthodox Cathedral in all of Constantinople, Antioch, Jerusalem and Alexandria, and also have a higher score / more population than the Catholics thus establishing dominion over Rome.
That would be a much more challenging UHV (along with the Byzantine game in general) if the AI Arabs would also flip Antioch, Edessa and Egypt. At the moment it's too easy for the human player to bottle then up and kill then quickly.
Pretty sure the AI flip zones can be set larger than the human ones / made conditional on the start. I think that's definitely desirable for the Arabs, and arguably also Germany and Burgundy as at the moment France is too easy once the first UHV is done.
That would be a much more challenging UHV (along with the Byzantine game in general) if the AI Arabs would also flip Antioch, Edessa and Egypt. At the moment it's too easy for the human player to bottle then up and kill then quickly.
Pretty sure the AI flip zones can be set larger than the human ones / made conditional on the start. I think that's definitely desirable for the Arabs, and arguably also Germany and Burgundy as at the moment France is too easy once the first UHV is done.