Random thing came to my mind.
JarlFrank mentioned in one of his posts (either in this thread or some other 4X thread) the 4X-RTS equivalence. i.e. if you take the 4X genre to mean what it says on the tin (eXplore, eXpand, eXploit, eXterminate) then almost all RTS games are 4X games. Another thing mentioned by him (and a few others) is the example of Age of Empires in particular as an (early) attempt at a real-time 4X. As another data point, a few years later, actual 4X game designer Brian Reynolds (responsible for Colonization, Civilization 2, and codex favorite Alpha Centauri) would again attempt a real-time 4X and the result was the very Age of Empires-like Rise of Nations.
Well anyway, there was a Nintendo DS game (confusingly) called Age of Empires: Mythologies, which was an attempt to make a turn based Age of Mythology i.e. a turn based take on a real time take on Civilization, completing the circle.
I've not played it, but a quick look on youtube shows that while it probably does qualify as a 4X in the literal sense, the scale is more tactical. That said, the smaller *sense* of scale is really a psychological thing, not a mathematical thing. Mathematically, the scale is no different from maps in MoO. The only place where there might be a measurable difference in mathematical scale is the tech tree (probably not even present in this game), which again lends to my theory that tech tree is an important factor in determining whether a game is a 4X or not.
Anyway thought it might be an intersting game to consider in the discussion, and to play, as it looks quite cool.