Frankly, I suspect an eco-focused SU would have a period of decades where an army/KGB coup could happen at basically any minute, because reforming and greenstreaming the core regions would pretty much demand retreating from the periphery.
Good POD for an apocalypse timeline, actually.
I am doubtful. The army/KGB faction was actually pretty reformist. The coup of 1991 only happened when the Soviet Union itself was breaking apart - they didn't revolt when Eastern Europe was lost, they didn't revolt at Gorbachev bringing in market reforms, or uncorking the bottle of lies so truth could pour fourth freely, or when the Communist Party's monopoly on power was broken... But in 1991 when it looked like Gorbachev couldn't hold the Union itself together.
fasquardon