Jon is more stable but also more incompetent.
The best chance for Westeros is for them to become a United Kingdom of Westeros, no more Seven Kingdoms, and begin ever so slightly shifting towards something like a Parliament or Magna Carta.
In the books, there were times in the past where a Great Council (a "House of Lords" you could say) gathered to choose the next King, based on inheritance. Imagine they now all have to come together every 10 years, and choose a new monarch, not based on inheritance but on who they thought was best. That would be the ground-breaker. That would break the wheel... or at least allow the wheel to spin without needing violence or necessarily crushing those beneath. With a hint that, in a few centuries, maybe they'll have a permanent House of Lords, and maybe after that a House of Commons, etc.
Or maybe some other reform?
Or maybe they just all declare independence, and it's truly Seven (or Eight or Nine or Ten or More, depending on if you count the Riverlands, Dorne, Crownlands, Beyond the Wall, and other autonomous regions like Oldtown and Skagos) Kingdoms again?
It has been my theory for some time now that by the end there will be so many people dead (including Daenarys and Jon) that they're gonna offer Tyrion the crown, but he's just gonna say "nope" and walk away...
