Your logic appears to be inconsequent. If you argue that the statistics will be flawed due to differing division sizes per country, than the concept of MP that is currently in this game must be flawed, too. If the divisions of Country A consist of 12,000 men, and the divisions of Country B consist of 14,000 men, it would be, according to your argumentation, only consequent that Country A must use 12 MP and Country B 14 MP to build a single division. However, as far as I understood, every country will use 10 MP to build a division, although the absolute number of men in a division differs, depending on the country you play. That seems to be a little bit absurd, as the only logical explanation for such an inconsistency would be that 1 MP in Country A represents 1,200 men, while in Country B 1 MP represents 1,400 men, which makes the MP of Country B more worth than the MP of Country A.
Especially in the 1936 scenario a slight misrepresentation of the actual division sizes is not a tragedy, as the whole division setup of a country will become ahistorical due to the player and AI actions within months or even weeks. To say, for the sake of simplicity, that one infrantry division equals 10,000 men and they equal 10 MP is, in my opinion, totally valid for a game. I'm pretty sure that in the 1914 scenario you also had to abstract the positions of divisions and brigades and their actual strength, too, and that we won't see an exact and perfect division setup of all military units in the world as of June 27, 1914 that totally corresponds with history.