I was thinking on the "Topic: Industry buildings for Knights and lords." I liked the idea of Families or Nobles 'famous' for his fine craftsmen.
I have read this post, and I though more than a unit this would be Paraphernalia. Like healers or Scouts. You could buy ' Engineers' as you buy Healers.
mmm... of course this is probably not possible, but the Paraphernalia could be used too to buy specialized workers, merging this with the building idea of the other tread and make a full new 'family' of Paraphernalia?
armour and weapons craftsmen, engineers, etc...