Why can't vassals be realistic? I feel that we should implement a new "vassal policy" mechanic- we should be able to demand a certain amount of their income per turn (their ACTUAL income; not including their expenses, so we should be able to do this even if their income is below zero- all trade should work like this), or perhaps science, specialists, slaves, population, units (the master could demand that they build them if they don't have what it wants), setting unit quotas for their own armies, dictating precisely when they should attack enemy cities (again, this should be done with all war allies), demanding intelligence information, etc. In addition, I think that we could institute "reforms" in their own empire, changing their civics at will and perhaps forcefully putting a certain amount of the master's culture in each of their cities.
I'm also thinking that there could be a "loyalty meter" in each of the vassal's cities that would dictate how loyal that city would be to us irrelevant of the leader's attitude, such as refusing to cooperate with taxation or revolting. A city revolting would lead to other cities refusing to acknowledge the master's authority and revolting themselves (whereas crushing a revolt will buy you some extra stability), and the vassal's leader might eventually decide to save his empire and withdraw from your vassalship even at the risk of war. And yes, you would have jurisdiction in those cities to send in your units to maintain order without actually annexing them (if you wished to betray your vassal, you could, though). You might even want to keep permanent garrisons there in order to prevent revolts in the first place (although this might have loyalty penalties for that city in the long term).
Perhaps propaganda buildings (public school, radio towers, monuments) might be constructed in those cities at your orders, which would hurt loyalty initially but improve it over the long run and also increase your culture there. If you had a vassal for long enough and had enough units and resources to enforce your agenda, its cities might decide to join yours, in effect annexing the entire civilization (this is how it's been done plenty of times in history- steady cultural assimilation).
So my scheme would basically make vassalship what it should be- giving you authority, military and economic strength, and strategic wherewithal without forcing you to conquer anything, but providing the risk of the vassal losing interest, becoming angry, not cooperating, or building up an army large enough to free itself or pose a threat to your own empire if you don't exert enough force over it. That's how it should have been from the beginning; vassals were always a half-baked mechanic in BTS.
Also, this has nothing to do with vassals, but would there be a way to stop culture from disappearing immediately after a civilization is conquered, creating temporary unhappiness and a risk of reemergence?
What do you think about all this?
