The other thing that got my attention was this name drop here.
So this Chou Kotsu is being made to be a big deal. So who could he be?
Tinfoil theory time.
I think this Chou Kotsu bloke is going to be the grandson of the Zhao Great Heaven, Chou Sha.
Chou Sha is now the only Great Heaven whose character has not been explored and this Chou Kotsu fellow might be the bridge between the long deceased Chou Sha and the new generation of Generals just as Gyou'un and Chougaryuu were the bridge for Rinshoujo.
Interestingly, historical Chou Sha (Zhao She) did have a son called Zhao Kuo. Zhao Kuo has actually been seen in Kingdom in a flashback. His name in Kingdom is Chou Katsu (which looks pretty similar to the newly introduced Chou Kotsu) and he was the Great General that replaced Renpa during the Battle of Chouhei only to get immediately cobbled by Ouki in one blow.
If my theory is correct then Chou Kotsu might be a character who is seeking to clear the family name of his father's blunder and return the family's prestige to the golden days of his grandfather Chou Sha, with some possible assistance from his grandfather's retainers.