Another question: does a non-Bolshevik USSR help or hurt German leftist revolutionaries? That may well be the biggest issue. Russia would have continued to fight the war longer, which probably means a faster and more complete victory in Germany. Russia also gets more of the spoils in Eastern Europe, since they’re part of the victorious coalition.
Does Russia develop as rapidly? Stalin’s, erm, gift to the USSR was the mass liquidation and conversion of human capital into industrial capital–which long term, might mean faster growth than if Stalin never was in power.