Realtalk, one of the biggest problems with the United States is that there’s no mechanism to adjust or reboot states after statehood.
In some of these cases the state would simply go under and be reformed or reabsorbed into neighboring states, but thanks to the federal mechanism this cannot happen. The US taxpayer will always be injecting federal money into the state and that’s enough to stave off total collapse, it is unpossible for even a natural disaster to push even the shittiest corrupt state under or anything else. And in many casss that means these corrupt ineffective states continue to linger on far past their actual shelf life and after they would have been reformed into a more stable one under any other system.
This also has the effect of crippling the federal government with a lot of “pocket boroughs/rotten boroughs” that have constitutionally-allocated voting rights yet have almost no residents and potentially no economic activity. And there is no mechanism to reform this without the consent of the states, which will never be given for political reasons even if the states themselves wanted it (which they don’t).
It is also not a coincidence that when the Slave States left that the north got a bunch of regulatory stuff passed while they were gone. The marriage is really not a happy one and part of that is that these state governments continue to be set up in an undemocratic fashion which continues to promote and empower these same folks over and over - like the 1910s/1920s and 1950s/1960s flareups of the Klan. But again, we rebuilt the same antidemocratic (by design, to suppress threats to oligarchic slaveholder power) government structures after the war and expected a different outcome somehow. And there just is no mechanism for reform without another war and re-admission to the union as being a club to force reforms.
This lack of a reform mechanism for state allocation and structure is going to be the thing that kills the union for good, I very much feel this is the singular underlying issue that’s been rattling around the untied states for almost 250 years now. Fix the state allocation and the senate or presidency aren’t as undemocratic a structure.
And yes, I understand full well that the slave states would never have joined the compact if such provisions were included. They should have been, and the slave states would eventually have collapsed or initiated a fatal war and been assimilated into a more stable structure. The economic collapse of the south in the 1840s/1850s as they missed the industrialization wave due to the Resource Curse of slave labor would have pushed them under in the alt-history timeline too.
(and yes West Virginia was the loyalists who stayed with the union, but, culturally and economically they have weighed with the rest of Southern Appalachia more in the intervening era, and suffered similar resource-curse economic failure due to coal rather than cheap slave labor.)