Fullscreen and resizing the window is already implemented. Not sure what you mean by adding a font on the countries.
So the country names are on the country (on the map) . And you could make a option to to form the imperium romanum as italy.
Sounds really cool, I don't know how you'd do that though. Maybe if you could find me a github repo of someone who did something similar?
Sure thing to #2
Sorry, I dont know how, the game is also without the font great. Maybe you should make the fights a bit longer, maybe improve the health of the divisions.
And I noticed a small bug, when you save the game and load in after it is slower and laggy. Maybe you could fix that.