As I understand it, the strongest Roman heavy infantry unit is the Urban Cohort, built using the Urban Barracks (requires Imperial Palace and Army Barracks to build). This is slightly stronger than the Praetorian Cohort, which requires an Imperial Palace.
Admittedly, I don't have it in front of me, but I don't think Legionary First Cohorts are listed on the Roman tech tree. I think you only get them as gifts.
If they do work like generals so much, is it possible that they gradually regenerate like general's bodyguards do (I think)?
I think there are too many "I think"s in this post. Never mind.
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