Techs don´t play a major role, because it´s a war scenario and you don´t should have much time for researching anything. There are so many other things to do. 
You can only reseach techs for additional support, for example the Anaconda plan. Union player can research it and setting up a naval blockade of all southern ports. I´ve some more ideas in mind, so the Darwins Voyage could be a good buildable wonder. I don´t know if it has effect when it comes via event.
Interesting thought about the governments. I agree that democratic governments are not so good for a war scenario. I´m thinking about Monarchy or Communism. I don´t like Fundamentalism because of the effects with the temples, churches and colosseums.
Using important peoples as wonders was one of my first thoughts when thinking about wonders. I denied it but maybe I should think about it again.
I´m tinkering with the idea of using Baloon Corps for the Union. They should get the Helicopter-flag and having a two space visibility. The Baloon itself can´t attack but ground units can it shot down. Also it will be only available via events.

You can only reseach techs for additional support, for example the Anaconda plan. Union player can research it and setting up a naval blockade of all southern ports. I´ve some more ideas in mind, so the Darwins Voyage could be a good buildable wonder. I don´t know if it has effect when it comes via event.
Interesting thought about the governments. I agree that democratic governments are not so good for a war scenario. I´m thinking about Monarchy or Communism. I don´t like Fundamentalism because of the effects with the temples, churches and colosseums.
Using important peoples as wonders was one of my first thoughts when thinking about wonders. I denied it but maybe I should think about it again.

I´m tinkering with the idea of using Baloon Corps for the Union. They should get the Helicopter-flag and having a two space visibility. The Baloon itself can´t attack but ground units can it shot down. Also it will be only available via events.

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