i have a few silly suggestions for this game
I. Permanent war / alliance options, where players can prohibit nations from changing their diplomatic status on their own.
II. Terrain, where each terrain has its own war speed, like mountains taking longer to conquer than plains.
III. Flag option, where flags are auto generated for nations and can be editted by the player, or completely disabled by the player.
IV. Language / culture options, where each nation starts with its own culture, can be renamed by the player, and can be spread over time to other nations and in its own territory.
V. Color that can be changed by the player, maybe something like a board with every possible color currently ingame that can be selected with a click.