One aspect of this game that I have always felt lacking was the pittence of XP you received from defeating AI units and armies.
Don't have much to offer here as the system that would be created would be a difficult task indeed, but perhaps a few rules of thumb could be implemented to help out:
- When an opponent hero is involved in the combat, grant double XP?
- When an opponent sovereign is involved in the combat, grant triple XP?
- When you wipe out an opponent faction --> Get fame reward and that last battle grants you quadruple XP?
Stuff like that....