Really cool game. I literally just came off EU4 to this and it felt so familiar, haha. I managed to beat it, though taking down that fortress was a turn 129 kinda thing. I really like the economy balance, and the mission per stage that requires a slightly different strategy each time. And the stories are all nice flavour to the world.
I love the aesthetic of ASCII games, but the keyboard-only approach can be a chore, and I feel some of your inputs/menus could have been a little better designed; like keyed options on menus to select an option quickly rather than scrolling down, enter, space and various keys all over the place is also a little awkward. But also I'm not familiar with the specific tech limitations of your engine, so maybe it's not so easy.
Sound was decent. It was there but I didn't notice it too much, which is the best balance really. :)
But yeah, sweet game!