I agree with everyone's points. France/Britain's Syndicalist revolutions are realistic, but the Second American Revolution/Civil War in my opinion would have been much better handled if there was no Pacific States of America in the game.
As for Russia, it would have been much better handled if there was no Siberia or Ural nations(I think that is new can't remember its exact name). If it was just Soviets vs the Russian Federation/a restored Russian Empire(which is dumb but an option none the less) and no foreign intervention(Germany can become super powerful if it intervenes and takes over vast swaths of Russia, either that or an event giving back seized territory to Russia would be nice)
As for Spain, I was fine with it really. In a reasonably more conservative Spain on the border of the Commune of France wherein the Carlists [historically] are disputing the throne I can buy a Carlist coup + Syndicalist revolution around that time both.
thus, I give Kaiserreich a 5/10, for being reasonably realistic, but with glaring historical flaws distracting from the game an crazy scenarios that keep it from receiving a 9 or a 10.