I have a relatively new Dungeon World game that I'm planning out a campaign front or two for, and I've found some inspiration so ideas shouldn't be too hard. My problem is that, should the players choose to pursue that story to its natural conclusion, there's a decent chance they'll decide, at the moment of truth, that the remnants of the royal family don't deserve to rule. I hope to have developed options for other people they can hand the kingdom to, preferably ones that will make it a difficult choice, but there is always the chance they'll decide to take the thrones.
I'm 100% ok with that, except that I have no clue what I would do at that point. Clearly, these will need to be adventurer-kings, and running adventures will only really change in the amount of support the players are likely to have. But when they want to direct their kingdom in certain ways or develop it in certain directions, some kind of mechanical framework would be really useful for representing the kingdom's changes...
I don't want to just "import" something like Pathfinder's Ultimate Campaign that really doesn't seem to fit in a super-narrative system like Dungeon World, but I'd like some kind of framework. Clearly, mechanics have their place, since there ARE rules for settlements; should I just track the settlements separately and give the PCs more control over settlement development? Or is there a good way to incorporate the kingdom as a whole?