This sounds really good.
While you are at it could you perhaps sort out the Nord peasant upgrade line. A couple of things are a bit weird, probably unintentionally so. For instance, A Huskarl can become Champion Huskarl or a King's Berserker, which one would have thought would be exclusively from the Berserker.
Also could you please give due consideration to troops that have restricted upgrade possibilities compared to another upgrade line and compensate their power accordingly. For example, as is currently the case a veteran raider can become a warrior and then on to the rest of the Nord upgrade line, or can (magically but I cant think of a way around it) become a Female Raider then a Shield Maiden, with no more upgrade possibilities. The power of a shield maiden is considerably higher than a skilled warrior (the male line equivalent rank) and is only 2/3 the cost. One might think this is imbalanced but I believe that her power should be slightly higher than expected due to her having no more upgrade possibilities. I would hope that this disparity is kept in in some form.
Good luck!