To be honest, I don't worry much about the ancillaries, especially in EB where the ones that give you command stars seem to have gone. However, the salient exception is the churigeon (sp?), which is very valuable - especially in EB, where you cannot retrain your army so easily while campaigning far afield. Incidentally, could you check what other ancillaries are incompatible with the churigeon? I have a very nice general but he is not worth taking to the field, as I can't give him a churigeon. I wonder if it is because he has a physician? If so, it's a poor trade, as the physician is pretty tame compared to the churigeon.
I really like the EB traits system, although my more successful generals seem to pick up the desert fighter one in the most unlikely locations (snowy Germanic woods etc).
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