I've never been a big fan of the conquest limitations, I've always wanted to build a ship without having to think to myself;"is this thing conquest friendly?", and it happens so many times that noone in the game has the item I need.
My suggestion is to add a scientist/research team that, like the secret police, you can give funds for them to unlock items that you either select, or get randomly, the more funds, the faster they'll research or the more times they'll give you new items randomly.
If you spy a city, maybe you can even steal their blueprints to learn them, or maybe, they can steal yours!
good ideas !
Agreed. That adds more strategic choices and interest to the campaign. Good idea!
Cool! Take notes david!