I'm surprised you're not upset about the identity of TC's rival. In TC's debut episode he referred to "her" as a he! OMG! Some, including Auman, suggested TC was lying which I say is crap! There was no good reason to & there was no way for us viewers to tell if he was. The best shows, animated or otherwise, don't make these kinds of mistakes! Plus, having him try to shoot Alopex was one of the worst things they could've done for his character! He's been dwindling since ELS & that took the cake!
To be honest, I thought it was a little cliché. The whole, “my arch rival is secretly my family member that I thought had perished is still alive and has found me again” thing has been used time and time again in story telling. It even happened in this exact before with Shredder and Splinter in the very beginning.
I probably would have been more offended had they not followed that cliché with the even more common, “you are my only family and I cannot go through with this even though I would have done it a few minutes ago had one of the other characters not given me some heartfelt advice” thing. That was worse in my mind, hahaa.