The Gastraphretes? I've heard about it before, but I am not sure how popular it was. AFAIK it was only used in Syracuse, and only for a short time. It was further developed into the ballista and similar siege weapons of EB's Hellenes and Romans, but the bow itself does not appear to have been a major weapon of war.
The team is rather short of modellers and there presumably still is a unit limit, so I think they are not interested in gimmick units. Unles you can show it was used extensively (or at all) in EB's time-frame.
Bookmarks