I see. This would probably have to involve both map changes and changes in the DB (for example, which regions border which would change). You're also probably going to end up picking winners and losers to an extent in the process. What stats does the merged region have? Which lord gets to keep his title? Which regions get merged? Seems messy, but maybe less heavy handed than many of the other suggested alternatives.
Fair point about region changes being little labour intensive. Though it could take months or it could take years for the number of nobles to drop off to an unsustainable level on a closed off continent. There might not be any need for intervention or if there is, not for a long while. In fact that's probably the biggest weakness of this method even if it feels gentler than some others. Closing off a continent to new characters might be helpful to character density elsewhere in BattleMaster in the long term, but it doesn't solve the problem today.
