The Klingons of the second season didn't come across as well as those in first and even third season. Granted in "Errand Of Mercy" the focus was on John Colicos and on Michael Ansara in "Day Of The Dove," but Kang also had his wife Mara alongside which added some extra dimension to the hints we were getting of Klingon society. Even the unnamed Klingon Commander in "Elaan Of Troyius" had a measure of presence in what little we saw of him.
Tigre Andrews might have done well enough if he had returned, but much like William Campbell he came across as something of an afterthought. Absolute minimal make-up and behaviour (including speech) that was just too human like watered down any real sense of distinct character and presence.