In the origional version of A&A, when Germany built 100% tanks it would only be a matter of time before Russia fell. The board was layed out in such a way that it only took tanks 2 turns to reach the Russian capitol, with Germany making almost twice as much money, and there being less territories in Europe, it would impossible for Russia to gain land anywhere.
Of corse in this revised edition, if Germany sends all her tanks through the north part of Europe, Russia can make a nuisance in the south east Europe area and force the attacking tanks to divert, which is what happened. It also took 3 or 4 turns for tanks to go from Germany to the Russian capitol in this version, which is ample time to build up defences in the proper area.
The main downfall of Germany came from lack of fighters. If Germany continues to produce fighters, they can continue to take down the UK transports and destroyers, leaving the UK forces landlocked, for the most part.
As far as the production of Russia goes, going by what Makh has said, Russia production is not what it should be. In the game, most of the russian territories that give the most production points are in the west of Russia. The Siberian area, where all these factories were built, produce only 1 or 2 IPC each turn per territory. Also the factories in the game are placed on the Caucus and on the capitol.
The thing is, I have no doubt the game designers were quite educated in all apsects of the war. There is the fact that they have to balance playability with history, and having rules like Russia increasing their production every turn would make the game more confusing. It's already pretty complicated for new players. As far as game play goes, it's much better for Russia to have factories on the capitol and in the Caucus because that's where the big battles are, and they want to be able to place new units in defence against Germany right on the spot instead of taking 2 rounds to move across the nation of Russia only to arrive too late
