To enhance your nation, you can just upgrade your buildings or increase your fleets' size, but they cost a lot. Instead of them, you can do some researches to improve your nation. The researches cost relatively less, and they can affect all your relevant assets.
There are 2 categories of researches in this game
- Development : You can unlock new items for your fleets. Cautious! these researches are only affective when you replace obsolete items with new ones manually.
- Enhancement : You can make your assets more efficient. This category includes upgrades of all weapons, facilities that you already have or will produce.