Please forgive me if somebody has already mentioned this, as i'm not about to attempt to read this entire thread, but the German civ, the only one I've played so far, has a serious mistake in it.
The Maus is slated as the next-to-the-last in the German tank line, with the King Tiger following it. The KT was produced around 6/44, while the end of the war had not seen a single Maus completed (5/45).
The Maus would also likely have been both stronger in offense and defense (almost impenetrable) but also slower than the KT.
Apart from that the game seems pretty interesting. I am wondering one thing though, as the readme doesn't elaborate, just what is the function of the German oppression hexes (those with the grayed swastika)? They seem to do alright when they're irrigated but sometimes don't even recognize mining.