An even more interesting AH would be if, at the time of the Acts of Union of 1707, somebody had said, “Hey, what about the colonies? Let’s give at least one seat to every colony, it will make them feel more, you know, included,” or however an English statesman of the day might have put that. At the time the colonies were so underpopulated that it would make little difference politically, but by the time of the French and Indian War, the American presence in Parliament would be significant. Probably American MPs would have demanded Imperial troops to protect British America and, after, it would have made it difficult to complain about slightly higher taxes.
Yes, the populations of America and Britain had fundamental differences that would have made it almost impossible for them to have a unified government. Britain at the time had what was essentially a ruling class - a hereditary group of people who were elected to Parliament and ran the government. Democracy in Britain meant that well off people could choose which members of the ruling class represented them in Parliament. But these well off people themselves generally did not get elected to Parliament any more than they could get elected King.
America didn’t have this class system. There was no hereditary ruling class in America. The well off people in America wanted a government in which they choose members of their own group to hold office and run the government.
So, this year, will Her Majesty be wintering at the White Palace or Monticello Castle?
And that is what the Dominion, or Kingdom, of America and all its provinces would have had – there might be an appointed Viceroy or Governor-General, but everything else would be elected --and what’s more, those well-off Americans could also elect representatives to go to London and sit in the Commons right next to all those snobs, haw!
Ok, this may not have inspired them to revolt, but what if they also found a way to become integrated into the Spanish Govt., and the French would still have revolted because conditions were hellish for them. It would have taken them a bit longer, but it still would’ve happened. Jackson would’ve joined the British military and still most likely went to conquer Florida.
Let’s move on from here.
I think the British recognized this issue existed. It’s why when they gave a degree of self-government to places like Canada, Australia, and New Zealand, they used the Dominion model rather than having these places send MP’s to the central parliament.
Well slavery would still have been a huge issue, but how it would have turned out would be somebody pulling a guess out of their ass. The various compromises of the early states started out of necessity to try to remain united against a common enemy, the English. With out that enemy would they have needed to compromise? Would there have been a succession of the south from the united English/.American empire? Or would they have been more afraid of the larger opposing force and just gave slavery up? If there was a succession war would it have happened much earlier because of lack of need to compromise? Or would Pro slavery representation of Southern states in Parliament prevent England from outlawing slavery till after 1834, or even after the 1860s?
Another possibility was the option of multiple Parliaments, or rather a Parliament and a Continental Congress. This was, after all, one of the colonists’ big issues.
The colonials had a huge issue with Parliament giving orders, and were very monarchy (up until, in their view, George the Worst stabbed them in the back). There was a good reason for this: they were all crown colonies. None of them owed Parliament a cent, and to the Continentals, Parliament was not some bastion of republican sentiment, but a bunch of upstarts lords* strutting around acting like they owned the place. The Continentals didn’t really recognize Parliament as a lawmaking body with authority over them. Only the King could do that.
Of course, in order for any of these hypetheticals to have occured, the British really needed to get rid fo their insane prejudices. As a group, the English upper classes had to be one fo the most prejudiced in history. Good Lord, Ben Franklin just weren’t “proper” enough for them - and this after Franklin had become a global celebrity. George Washington could easily have been a loyalist (had he been granted a King’s commission, it’s unlikely he would have felt free to rebel), except that the Royal officers sniffed and kept their noses firmly in the air about him - even though he was probably wealthier, more gentlemanly, and no less a commander than most of them. Though we can’t say exactly how much it affected things, British obnoxiousness no doubt contribued heavily to the Revolutionary War.
*Not all Parliamentarians were lords, of course, but many were, and even the Commons weren’t all that different.
I agree that the taxation was not the root cause, but I think that the representation was even less of a root cause. I’d argue that the root cause was the desire for western expansion that British treaties were cock-blocking, and that there was already a political and business class in the colonies in favour of independence for that reason, and the rest was just Glenn-Becking it out for the proles.
Maybe the past few years of paying attention to American politics have made me just a tetch cynical. 
Anyone who thinks that people won’t complain about quite low taxes that are lower than what people elsewhere pay without protest hasn’t been watching the news the last few years.
There would have been a French revolution even if their had not been an American one. A population could only stand so many bread shortages, regressive taxation and the merchant middle class coming from abroad telling everybody how much better things are elsewhere before something snapped.
I think this is correct. Keep in mind the American colonies’ charters dated back to the 1600’s during a time of greater royal authority. In the American’s mind, the King gave them their own assemblies which were equal bodies to Parliament. Of course, the idea of the King as ultimate sovereign was obsolete in England post Glorious Revolution when Parliament definitively established itself as the true sovereign.
A good constitutional compromise would be the creation of a new American Parliament for the Kingdom (call it that, not a Dominion, to recognize constitutional equality) of America; plus a new Imperial Parliament, meeting in London (at least to start with), sovereign over all and with representatives from all parts of the Empire, and a new Imperial Government separate from the British Government. The Imperial Government and Parliament to have jurisdiction at least over all matters of foreign policy, military policy, and trade within and outside the Empire. Oh, and the King takes the new title of “Emperor of the British Empire” or “Emperor of the British Isles,” in addition to “King of America,” where he is represented by a Viceroy, who has about as much power – and prestige – in America as the King has in Britain. America would be a good place to send a Prince of Wales to give him something to do. (Remember that tension in The Madness of King George?)
I agree western expansion was a major issue but it was seen as a representation issue in America. Americans resented the idea that a government on the other side of the ocean could tell them where they could live.
The British were never going to please everyone. Even if Americans were in Parliament, they’d be getting outvoted by Britons. But American representation would have co-opted some Americans. Radicals like Adams and Hancock would have still tried to drum up rebellion. But moderates like Franklin and Washington probably would have stayed loyal. But the British shut out all Americans so that created a sense of American unity.
Whatever happened, it would not be like the world of The Two Georges, by Richard Dreyfus and Harry Turtledove, where, whatever compromise George Washington and the American delegation worked out in London in the 1770s, it apparently did not include Parliamentary representation, nor change the essentially top-down nature of the British-American relationship. (Governor-General Sir Martin Luther King is anxious that if the painting “The Two Georges” is not recovered, “London will not trust us to run our own affairs.” Therefore, apparently London doesn’t, constitutionally, have to let the NAU run its own affairs, its autonomy is always on sufferance.) I mention this only because this novel is one of the more thorough literary treatments I’ve seen of the AH premise of America remaining in the British Empire, and the only one with the Revolution averted rather than lost; but, I’ve never seen an AH novel based on the OP’s premise.
But if there were no Revolution, the Americans (including a significant population who, in our timeline, were Loyalists when the Revolution came and had to flee afterwards, many to Canada) could raise no objection to being styled “the Kingdom of America,” republican sensibilities notwithstanding. They would gladly accept monarchical form in the system so long as there was some democratic-republican substance. Besides, it might make them all feel a bit less provincial, if the Viceroy keeps a sort of Court and everything in the capital (probably Philadelphia, maybe New York). And it could it become a tradition that, at appropriate age, the Prince of Wales would sent out to be Viceroy of America – get him out of his father’s face and vice-versa, and give him some reigning-experience in the field before he takes the throne, being Viceroy of America is almost as good as being King-Emperor and a whole lot more fun. But, as in the UK, the Viceroy would have some power of appointments, but the real power to make political decisions would rest with the American Parliament and a Government answerable to it.
Another question is how the Indians would fare, if the American expansion westward had British noses and fingers in it at every stage. (Dreyfus and Turtledove picture them as having fared better, and some Indian nations have what amount to their own large autonomous provinces with traditional systems of government and chiefs – like the Indian princes who, in our timeline, were left in charge of those parts of India the British Raj did not rule directly.
For that, just look north. Not nearly as much violence, but still a comparable level of eonomic and social marginalization that has left us with one hell of a mess.
Except that the colonies’ letters to parliament, as in the Declaration of Independance, comparatively little space was spent on on the issue of representation per se, and much more on the taxation and numerous other issues. It’s hard to read the D of I and get the impression that these people would be OK with quartering troops and all the rest if they could just get seats in London’s parliament.
Earlier Thread: Did the UK even Consider Giving the Colonies Representation? - Factual Questions - Straight Dope Message Board
And just imagine Rudyard Kipling growing up in the Wild West instead of British India . . .