Pretty interesting to have ideas like that in your head than a quick one-off scenario, so good job indeed.Thank you! Hopefully more will be coming this weekend. I'm trying to get research done on some early scenarios to take to a full alt history once my current project is done.
I think that's my bad on the wording I chose. I meant that "French Concession" and "Spanish Concession" were both to Britain. I need to fix that.
I'm hoping to tease the scenario out a bit more and get it somewhat realistic. I have the "Revolutionary Period" somewhat mapped out into three distinct eras, the first from 1765 ending with the failed First American Revolutionary War, which this map shows. Then the second which is an interwar period with significant strife... the British win big with all the territory they get and don't trust the colonists completely... and the colonists completely disregard British laws and just begin settling in Indian territory, sparking all sorts of nasty Indian-Colonial attacks, British law enforcement actions which alienate the colonists, etc. etc. in a vicious cycle. The third period is the lead up to the Second American Revolutionary War, which is successful... then a possible "fourth era" where the US falls apart due to the Articles and separates into the USA and Commonwealth.
I'm toying with the idea of including Upper Canada in the Second Revolution and eventually having the US expand into the Pacific Northwest since the Commonwealth (and a few others) lock the US out of the Gulf of Mexico and southern California. Essentially the British don't see the point in another costly war when they can just trade with the colonies and refocus on Europe and India and China (which started to happen anyway).
Lots of butterflies and ideas... already mapped out a few US-CA wars involving the Mississippi River and tolls, West Virginia, and a few other things.
Some of the leaders like Hamilton manage to escape British justice and then come on back to America... and a lot of Patriots who are "exiled" come back and basically become what we'd call terrorists; burning ships, attacking British garrisons, raiding the treasuries, etc. etc.
I can see Upper Canada and OTL Loyalist-settled areas becoming part of the second USA, indeed all of English Canada. Why not? Most Loyalists in Upper Canada were Late Loyalists/Americans settling without any special ideology, political conditions got them revolting in the 1830s in reality, local British governors JUST AFTER the Revolution noted the Loyalists moving into the Maritimes were bitching on getting better local government more than the original New England Planters ever did (and they had SOME rumblings of sympathy for the Revolution way back...) and in TTL I don't see why they'd escape any harsh British rulings or decrees since there's no USA-Canada divide in the first place with the USA not existing at the time - doubly so if British law extends into the Great Lakes area, which Ontario is definitely part of geographically. That and what you said regarding British monentary profits without direct costs of control. It'd be easier to toss everything inland (Canada, eh) and even the PNW to America if it takes so long to get to the Pacific, much less trying to get inland without the Eastern Seaboard or Gulf of St. Lawrence to sail in from.
Since you seem to be going for a North-South divide, having the North/USA take everything at least north of 36'30/the 37th parallel including that Upper California Purchase line I noted works well enough. Southerners can politically shuffle just south of Missouri (which definitely had plenty of Southrons and slaves settle it alike, but then it all gets mixed up with lots of Mid-Atlantic settlers and Germans swamping them demographically outside the Ozark plateau part of the state) and then Kansas westward as in OTL. West Virginia was also settled by southerners, but it was so slave-empty and of course across the Appalachians of course it'd be a bit of a hotspot even outside the economic issues of being within Virginia itself.
Just to also throw stuff into the mix, you can still have a lot of sympathy for the colonists within Britain both commoner and MP alike to hamstring a lot of the really harsh punishments outside the initial martial law - that they DIDN'T become independent and fought for 'Rights of Englishmen' would resonate with a lot of people, especially when they are still nominally Englishmen.