I don't quite know the reasons why, but I love the Roxolani Rider unit. They seem like the perfect medium between very stylized and raw, strict historical accuracy...and I suppose that my pathetic, slobbering-fanboy love for nearly all things related to the nomadic tribes from the steppes, particularly the mounted archers and lancers, could very well be a factor.

Even still, of all the nomadic cavalry units (all of which look amazing and are fun to use), there is something unique about their overall balance with regard to game play. I love that they don't wear a lot of armor, since it places so much more emphasis on their posture and grip during a charge with the kontos (kudos to those who designed that animation), and the fact that you really have to be careful about pulling them away from the enemy once their charge is through really accurately represents (IMO) how the ancient lancers fought.