That's why I've started to review each civilisation (although maybe I'll give up before going through all of them), pointing out mistakes and proposing relevant additions concerning the time period of the game (with preceding important characteristics taken as Civilisation Bonuses), while quoting authoritative sources, not with the idea to use necessarily everything, but to take from there. For now I've only done it for the Spartans, and the Athenians are coming soon, but it's a very slow and consuming process: I think for the Athenians I've gone through 3000 to 4000 pages of books and papers over the last few weeks, and all that has to be translated to what can be used in a game. One of the reasons historical RTS like AoE were so successful is that they actually taught something.