The Brave New World expansion brings a lot more to Civ 5's table, making the late game contest for ideological dominance an important factor in claiming victory. In addition, the expansion also revamped the cultural and diplomatic victory conditions to make them more of an active struggle against other empires.
However, a week after release, it seems to me that diplomatic victory isn't quite enough of a contest when dealing with the AI. Unless another player is directly contesting you for control of City States (presumably also going for a diplomatic win), it is easy enough to turn the diplomatic victory into an economic victory by buying up City State allies and their votes. As the cultural victory was made more interesting by tying it to the concept of ideologies, adding a similar system to the diplomatic victory will increase its strategic depth and act as a barrier to uncontested diplomatic dominance.
I suggest that each City State be assigned to support one of the three ideologies at the start of the industrial era. As it is already easy enough on low to medium difficulties to gain City State influence, these preferred ideologies do not provide any bonuses, but instead act as a small penalty to unaligned civilizations.
Diplomatic penalties for City States which do not share your preferred ideology:
1. City State Favor decays at double (x2) the original rate, to the normal resting value.
2. If a City State is allied with a country which does not share its ideology, it provides 1 fewer delegate in the world congress.
These penalties will make it much more difficult for a single civilization to quickly rush-buy the favor of City States and use their influence as a voting block. However, this is not intended to be a permanent issue for people seeking a diplomatic victory or influence over their neighbors. The preferred ideology of City State can be influenced by other civilizations, removing the unaligned penalties while applying them to your opponents.
A City State's ideology can be changed in 4 ways.
1. If you're currently allied with the City State, they will adopt your preferred ideology for a nominal fee. This will require some playtesting, but I suggest 500 gold. This is the typical rate of buying a City State's favor from friendly to allied, and a rich empire late in the game will not have issue affording the fee. It will just take a few additional turns to achieve it.
2. A City State may be threatened to adopt an ideology, using the existing threaten mechanic. This decays their favor with you, so it is more helpful when you want to deny votes to opponents which are allied with City States in your sphere of influence.
3. You can also use your spies to influence a City State's preferred ideology.. Rigging elections would have a chance, depending on spy level, (25%, 35%, 50%) to sway the City State to your ideology. Likewise, performing a coup on a City State automatically causes them to adopt the ideology of their new ally.
4. Declaring a world ideology through the World Congress will change all City States to the selected ideology, eliminating all penalties related to ideology unless the law is revoked.
Coding the AI use these new mechanics effectively would probably require more tools than a modder has access to, but I would be interested in giving it a shot if that is not the case. The suggested effects may seem somewhat insubstantial, but they're merely intended to add depth to what is already a well developed influence system. It also elevates the importance of ideologies in the diplomatic victory, from merely providing favor bonuses to being the key to gaining votes in the world congress and limiting your enemies influence.
However, a week after release, it seems to me that diplomatic victory isn't quite enough of a contest when dealing with the AI. Unless another player is directly contesting you for control of City States (presumably also going for a diplomatic win), it is easy enough to turn the diplomatic victory into an economic victory by buying up City State allies and their votes. As the cultural victory was made more interesting by tying it to the concept of ideologies, adding a similar system to the diplomatic victory will increase its strategic depth and act as a barrier to uncontested diplomatic dominance.
I suggest that each City State be assigned to support one of the three ideologies at the start of the industrial era. As it is already easy enough on low to medium difficulties to gain City State influence, these preferred ideologies do not provide any bonuses, but instead act as a small penalty to unaligned civilizations.
Diplomatic penalties for City States which do not share your preferred ideology:
1. City State Favor decays at double (x2) the original rate, to the normal resting value.
2. If a City State is allied with a country which does not share its ideology, it provides 1 fewer delegate in the world congress.
These penalties will make it much more difficult for a single civilization to quickly rush-buy the favor of City States and use their influence as a voting block. However, this is not intended to be a permanent issue for people seeking a diplomatic victory or influence over their neighbors. The preferred ideology of City State can be influenced by other civilizations, removing the unaligned penalties while applying them to your opponents.
A City State's ideology can be changed in 4 ways.
1. If you're currently allied with the City State, they will adopt your preferred ideology for a nominal fee. This will require some playtesting, but I suggest 500 gold. This is the typical rate of buying a City State's favor from friendly to allied, and a rich empire late in the game will not have issue affording the fee. It will just take a few additional turns to achieve it.
2. A City State may be threatened to adopt an ideology, using the existing threaten mechanic. This decays their favor with you, so it is more helpful when you want to deny votes to opponents which are allied with City States in your sphere of influence.
3. You can also use your spies to influence a City State's preferred ideology.. Rigging elections would have a chance, depending on spy level, (25%, 35%, 50%) to sway the City State to your ideology. Likewise, performing a coup on a City State automatically causes them to adopt the ideology of their new ally.
4. Declaring a world ideology through the World Congress will change all City States to the selected ideology, eliminating all penalties related to ideology unless the law is revoked.
Coding the AI use these new mechanics effectively would probably require more tools than a modder has access to, but I would be interested in giving it a shot if that is not the case. The suggested effects may seem somewhat insubstantial, but they're merely intended to add depth to what is already a well developed influence system. It also elevates the importance of ideologies in the diplomatic victory, from merely providing favor bonuses to being the key to gaining votes in the world congress and limiting your enemies influence.
