I wonder if it would be worth adding the option of giving the player a starting manifesto (or the possibility of a starting manifesto, depending on the country being played and the player’s settings) - these represent the election promises the party made before getting into power (which presumably helped them win that first election in the first place), and would have the same effects as the standard manifesto - either make good on your promises or gain voter cynicism. It might be a nice way of adding variety and challenge to the game.
Presumably the starting manifesto would be a starting condition like other aspects of the nation (so Cliffski could create appropriate promises for the game’s built-in nations, whilst modders could add their own for mods). Alternatively they could be random, or limited-random - the game/mod developer chooses a list of suitable promises and then how many of those are actually selected at random at the start of each game. So a developer might list the options as cutting income tax, abolishing car tax and increasing equality, then note that any two of these should be selected at the start of each game.