1. ability to trade with a country using a specific road.
2. water supplies
I'm making these suggestions in a single thread, because they imply the same thing: strategic advantage.
First of all, trade routs would make the suburbs sometimes more important than cities. Next, trade agreements would force the players to do some diplomacy. It is impossible to survive in 21th century without diplomacy, whereas many players do absolutely no diplomacy in the game. The concept of trade agreements will change many things. Real example. China has started the project of his silkway, and it has such a big strategic importance that a lot of countries are competing to get the road pass through their territory. Players who do actually play with a strategy will get significant advantage, this is more realistic, more fun, more intense and more brainwork will be needed (which's the reason I love this game). + I think it will be add an incredible balance to the game.
In addition to this idea, you could add more importance to energy in the future, so people will have more reason to fight for oil.
Next. Water supplies are extremely important. They just have a huge strategic importance. By adding these features, players will have to develop a strategy.
P.S. I understand that such features may complicate the game, and many people don't like complicated games, so this might be unprofitable for you.
2. water supplies
I'm making these suggestions in a single thread, because they imply the same thing: strategic advantage.
First of all, trade routs would make the suburbs sometimes more important than cities. Next, trade agreements would force the players to do some diplomacy. It is impossible to survive in 21th century without diplomacy, whereas many players do absolutely no diplomacy in the game. The concept of trade agreements will change many things. Real example. China has started the project of his silkway, and it has such a big strategic importance that a lot of countries are competing to get the road pass through their territory. Players who do actually play with a strategy will get significant advantage, this is more realistic, more fun, more intense and more brainwork will be needed (which's the reason I love this game). + I think it will be add an incredible balance to the game.
In addition to this idea, you could add more importance to energy in the future, so people will have more reason to fight for oil.
Next. Water supplies are extremely important. They just have a huge strategic importance. By adding these features, players will have to develop a strategy.
P.S. I understand that such features may complicate the game, and many people don't like complicated games, so this might be unprofitable for you.