I have played of CK2 since 2017 and I have seen border gore in Byzantium, even after Holy Fury and Imperial government. Byzantium, same as Roman Empire were a centralised and orderly state with a themes. In CK2, there are a themes too, but in CK2 themes (minor viceroyalties) are disorganised and viceroyaltes (exarchates in Greek, proconsuls in Roman) have often revoked minor viceroyalties titles (sometimes even counties). In real Byzantium there was no revokation any lands by exarchs, only emperors did this. I wait for repair this problem in CK3. In CK2, even if you forbid vassal wars, viceroys outside your de jure empire changed vassal war law and waged wars. This led to the situation when viceroy/minor viceroy has title outside their de jure lands. I understand that in feudal Europe de jure borders and centralisation no matter, but in nominally bureaucratic and centralised Byzantium, in game vassals was truly only administrators of lands.
My propositions:
1. Viceroyal titles should be inherited always by emperor, even if viceroy/minor viceroy has a children or (in case of minor viceroys) be a vassal of higher governor.
2. If emperor forbid vassal wars, even external, viceroys outside the Byzantium de jure should not change the vassal wars law and wage war.
3. Viceroys should not revoke the lower vassal titles.
4. Viceroys and viceroys' children can't inherit any titles outside his parent viceroyalty/minor viceroyalty (I have seen situation where viceroy of Sicily controls province in Africa).
5. Viceroys and vicereines should not get married with another viceroy to prevent situation where child controls two or more viceroyalties.
My propositions:
1. Viceroyal titles should be inherited always by emperor, even if viceroy/minor viceroy has a children or (in case of minor viceroys) be a vassal of higher governor.
2. If emperor forbid vassal wars, even external, viceroys outside the Byzantium de jure should not change the vassal wars law and wage war.
3. Viceroys should not revoke the lower vassal titles.
4. Viceroys and viceroys' children can't inherit any titles outside his parent viceroyalty/minor viceroyalty (I have seen situation where viceroy of Sicily controls province in Africa).
5. Viceroys and vicereines should not get married with another viceroy to prevent situation where child controls two or more viceroyalties.