Perhaps I’m missing something, but I think that Germany could end up with 24 inf, 5 art, 3 tanks and 3 AA in East Poland on G2. 35 units with a power of 67. This assumes the armor in S Germany and the mechs in W Germany go to France.
The Soviets can counter with 19 inf, 2 mechs, 8 tanks, 2 art, 2 fig and a tac. This is 34 units with a power of 61.
The odds I’m getting are 62% for the Soviets. Despite having a slight advantage in numbers and power, the Germans (after the AA are gone) are losing more valuable units from the start and this quickly shifts the power advantage to the Soviets.
And often, even when Germany is setting up for a G2 into East Poland, they don’t quite have those numbers and the odds are better for the USSR. The Germans send an inf into Bulgaria, lose 1 or 2 in strafing Yugoslavia, and/or send 1 or 2 to Norway. Of course, the German player can also set up for a more aggressive move into the USSR by pulling some other units that would normally go against France back or building mechs and tanks on G1. But the Soviet player can see that before deciding on their build.
I don’t have enough experience to judge it yet if this is a good build if you can’t discourage the Germans from going into East Poland but I think it might be. A more mobile and offensive component to the Red Army forces the Germans to keep their stack together as they move towards Russia and then limits the income they can grab (and deny the USSR).