The thing is that the largest army a teuton can build is never as strong as what a roman can build when resources aren't an obstacle. In the endgame when all the easy farms have deleted their accounts, things start to even out as farming gets harder. Granted, teutons get their armies a bit faster, but a good roman fist is more scary than a teuton fist. One favouring factions that romans can use their cavalry defense unit, legionnaire, to augment attacks performed by imperians. This way, romans are balanced out between offense and defense as the roman triumvirate of legionnaire, praetorian and imperian offers good options for roundabout play.