Hydrosalpinx
Am I the only one who thinks a mostly water map would be fun? Throw in a bunch of islands of varying sizes and have an island hopping campaign. Maybe add a few islands that are packed with extra resources to slightly boost the income of whoever controls them.
Also, would adding terrain features to a later version of the game be too difficult? Add terrain such as mountains, deserts, marshes, etc.. All of which would slow troop movement and some mountains forcing units to go around or through a narrow pass.
I think that would add to the strategy of the game by making it valuable to control certain geographical areas, such as mountain passes where enemies have to bottleneck to get through.
I thought of a way to do Mountains, by perhaps have one square, split into four squares? Forcing a unit to get off perpetual attack, navigate a path through the mountains, so to speak. And also taking longer to conquer the area.