@ Ivan
The "Dark Ages" weren't dark (not for Europe, and most certainly not for the rest of the world), and "post-modern" is an oxymoron (it is impossible for people to live in any time that is not the present, hence "after the present" doesn't make sense), though I agree that more ages should be added. However, you might want to split up the Ancient Era into Ancient and Classical, which segues into the Imperial Age, then a period of Middle Ages (since the Midieval Period in Europe was a time of transformation from the old, broken, Roman institutions, into the ones that we are more familiar with), Renaissance is a little questionable (its a highly inaccurate, though commonly used, terminology) so I would suggest replacing it with Reformation and Enlightenment, which then leads into Neo-Imperialism and finally Industrial, Modern, and "Space Age". Additionally, unless the game wants to add Jesus Christ, the dating system really should be changed from BC/AD to BCE/CE.
As for future techs, really all they need to do is update the game with more current technologies. I mean really, technology has been expanding at an amazing rate even before the Industrial age ended but the Modern age in Civ3 has the fewest number of technologies. More work definately needs to be done here (and since Humans aren't close to colonizing other planets yet, the Space Ship needs to be moved towards the end of the tree, if not as a bonus for the 1st "future tech")