Saw this when first asked but was hoping someone with some solid info would help you out. Sorry if it got overlooked friend!

So, I have not seen it printed, but yes I would imagine you still need the adequate story points required to take over a high ranking npc, even if you were given the code, (or be starting with a pledge package of adequate rank although this only applies to launch) otherwise Kings could just switch between two players with minimal requirements, and the system would be broken.

Recruitment for the most part is happening based on current titles held, and based on the fact that during Exposition while we are creating the world we can do a lot more.

For example, if a King was going to marry someone that had no pledge package, and effectively make them the Queen, this person could make a Ward for all it mattered, and when the King marries them in Expo they are still a queen, no questions asked. (Out of Expo too, tbh, although npcs might find it controversial)

A lot of people prefer starting their own families, and at this point in the game development this might be for the better, but there certainly is a market for a group of friends to come in and all be part of the same family as long as they met minimum requirements, or had the proper pledge packages to do so.

Yeah I believe there was a dev blog that talked a little about that, I forget which one.