Honza,
Your maths is way off. Because reserves have to be 6 hexes from the front lines and because there are numerous German salients, the number of places where you can put reserves is very limited. And because the Germans are in places only 9-10 hexes from the Volga, you can't afford to not man the front lines. The German player can ignore the reserves pretty much until the Russian at start forces are destroyed or broken, and then engage as many or as few of them as he wishes.
So it's 7 Companies vs 3 Companies. As a Russian paying +2CPP to set a Company on map when you only have 12 CPP in total is a big call. It means giving up vital OBA, fortifications or a third company. Russians coming in as reinforcements are at a disadvantage as the entry areas are very much at the north and south and the Germans get Stukas. That auto-pin is going to stop you moving stacks quickly in open ground, never mind the MG's and bombs. The German reinforcements may well get to the front line before the Russians do as they can move freely behind the lines.
But comparing companies understates the difference. Apart from a single 8 squad pioneer company, all the German companies have 12 squads and only deplete on a 12 (1 in 36). At least one Russian company is a SMG company (9 squads) while with only 12 CPP its likely at least another 9 squad SMG company will be bought as they are cheaper (4 vs 5 CPP). And all the Russian companies deplete on 10+ (6 in 36).
The relative cheapness of Russian infantry (5 vs 7 for a Rifle Coy) is not very important because the historical modifiers mean the Russians can only buy 2 Coys on Dates 2 and 3 and 1 Coy on Date 4 and 5. The Germans can easily match or exceed that. And its not enough to replace the huge losses the Russians will suffer on the first date. They are re always going to be behind the curve.
The reduced leadership and lack of HMG's is a good thing. It makes a much better game and would improve Red Barricades IMO. I think the change slightly favours the Russians but it's nowhere near enough.
Also you've basically made an argument because it doesn't look balanced, that must mean it is because it's been playtested so much.
That isn't even logic.
Sorry to rant. I get you like Stalingrad and MMP (I do too) but play it and see how you feel then.