Actually the KR CSA does have considerable friction in the flavor events now--ironically more so than the other factions because the Reds have gotten the most love. (If you play Huey, Huey comes off as a lot better of a leader and person than he probably would be IRL, and the most flavor comes if you pick Pelley and he turns America into a decaying KKK shithole)Avoid:
- Social norms suddenly bouncing from 1930's to 2010's as a result of the revolution (Looking at you Reds!)
- Everyone being portrayed as willing to go along with the new regime (See above)
- Open dissent is tolerated and there is no friction to radically restructuring the whole economy (Looking at you Kaiserreich CSA)
- Libertarian Socialism suddenly working on a great level with no public blowups (Looking at you Reds! again)
- The USSR being recreated 1-1 (Because this is America, and the population isn't starving illiterate peasants)
- The "Whites" all being frothing-at-the-mouth fascists (Looking at you basically every Red America TL)
- Cast historical figures that were general careerists as finding their place under the new regime
- Show the rough transitition period from A to B
- Write about how the new regime appropiates the old decorum of Old America to fit their purpose
As to OP's question; I think that there are a number of ways to do it with a number of PODs. The normalization of left-wing views early on (Bryan somehow successfully courts labor in 1896, wins, the left becomes a dominant force in American politics in the late Gilded Age?) could cause eventual reform of the American system along libsoc lines. If you want a more authoritarian setup, violent revolution in the interwar period due to some sort of tragedy of errors stemming from some bad decisions in or before WW1 is probably the best way to do it.
I really like the story of a Reed-victory or Olson-couped Commonwealth of America in Kaiserreich's current build myself. As to why:
- The Reds in a Reed-victory scenario are sort of the legitimate faction, standing for a President who was couped by a treacherous egomaniac who jumped the gun and threw the nation into chaos. In an Olson-couped scenario, they and Huey are fighting against an oligarchic junta that betrayed the very foundations of America itself in the name of the dying system as it stood, right on the cusp of salvation. Both of these give the revolutionaries the moral standing to plausibly win due to military defections and national chaos.
- The Reds have a senior military officer and significant numbers of military defectors on their side. This gives them military expertise to support their advantages in manpower and industry.
- The Reds explicitly call back to the American Revolution and call their forces the Second Continental Army, because most of their supporters like the idea of America and just want to make it better for everybody rather than to tear it all down and replace it with something else like your average Joe in state that's been a crappy authoritarian regime for decades would.
- Even if you are really really good at the game and can win the war by Christmas '37, America is still left a broken wreck that takes years to recover. And you're dealing with pro-MacArthur and pro-Huey terrorists for most of that.
- There is an "old America" splinter state in the form of the PSA (which if I were a dev I would redesign as the "Pacific Defense Command of the Several Free and Loyal Democratically-Organized States of the United States of America", a legitimist organization explicitly dedicated to the reform and support of healthy American democracy) that is often willing to rejoin the successor state of the USA if it is actually a democracy, and will fight back if the new America is authoritarian. This will bring a significant force of participatory moderates into the fold and present some variety to the politics and challenges to the new political establishment.
- Tying into the above, it's effectively canon that hardcore anti-socialist forces are resolutely abstentionist. It will take decades for the new America (if democratic) to live up to its promise of participatory democracy.
- Even within a democratic Red America, there are explicitly significant challenges to progress. Elizabeth Gurley Flynn can get the new Congress to redistribute wealth from the Vanderbilts and the Fricks and the Morgans, pass laws banning racial and sexual discrimination, leave a wide-open exception in the Family Code that technically legalizes homosexuality, and otherwise tack socially left as far as she likes, but she still has to deal with:
- A scandal involving a documentary finding white union bosses trying to charge double dues from black members
- Women trying to set up gender segregated unions after experiencing workplace discrimination as others object to the very concept of women-only unions
- Years of terrorist attacks by MacArthurite and Longist diehards
- The Klan, which mostly got killed off in the war but still supports Southern terrorism with what it has left
- An economy that remains in the shit for years even as she tries to comprehensively restructure it along anarcho-syndicalist lines.
- And if you pick Norman Thomas, the exact same thing happens except he's more openly pacifist.
- Canada is hyper-militarized and hates the Reds (yes, they are a shitty authoritarian craphole running well beyond what they can sustain while led by a bunch of idiots who think they're still a world power, but they have a big military and it's aimed south)
- In any MacArthur coup scenario, the junta wearing America's skin like a grotesque mask has no legitimacy beyond what it can buy with its corporate backers' money and seize with its arms, making the revolution a lot easier.