thinking new factions is very hard if one uses all tech and other all the magic
If you take a look at the background, it´s said that everyone in Glest´s world has the potential to develop magic abilities, and the mages themselves were great scholars too. It was by means of a historical process that some people "lost their touch" with magic to a point where they thought it was fake or evil, and it seems clear that some of the leaders of those people made use of the situation in their own favor to get rid of the mages, which ended up in a big split and a war. But we have just begun to explore the core of the matter so far. Everyone has a strong disbelief in magic as long as you stay in the cities, but as soon as you move to the countryside things start to change, and the farther you move, the more you realize how people still feels magic, though not everyone would admit this (even less if they get recruited, the first soldier who lit a fire with his finger is still hanging somewhere). So this is not a black and white world where every single techie will fight every magie to death. There could be several different "pure" magic and technological factions belonging to different places, with different units. And the war, again, is mainly but not only about tech vs magic; some greedy landlords took advantage to start a war with the neighbour and some evil mages fought against their fellows too.
Even more (sorry for the long paragraph!): if we raise our sight above the mountains, what other societies could be awaiting to the other side? maybe ancient tribes with fierce warriors, primitive technology and some magic abilities, people which still respect their (very few) magicians?
As you see, there´s a lot of room for this world to grow. Now you may ask, ok, then why I only see in the game two opposite factions with only a handful of different units? ...
if we could, if we could...