Is that so different from the situation of the American colonies in the British Empire back in the 1770s?
It isn't. DC contributes quite a bit of tax revenue, but has very little say in its administration. Congress can overturn any local law. Also, no matter what the population of the city ends up being, it can have no more Electoral College votes than the least populous state, which is ludicrous.
Puerto Rico, of course, has it worse. Congress has full jurisdiction, and while there is no Federal Income tax, Federal rule can and has had large impacts on state economy, and, of course, with issues like Hurricane Maria. Nor do they get to vote for President, so they are even more disenfranchised compared to residents of DC.
Would it have been only 1 to 2 MPs?
Either way, the more obvious answer was Dominion Status, which the Brits didn't come up with till much later. I doubt the US would have accepted it. India didn't either, and several other countries rejected it.
