Verminator X alsways seemed so cool to me as a kid (of course Shredder did too). I only had a couple of issues with him but hey he was a cruel mutant feral cyborg genious with an attitude who's from the future, so what's not to instantaniously love?
I do remember the bird-guy showing up later in the series, as he, the turtles, a tiger-guy with lots of arms and a blue twi'lek lady fought some giant mind controlling demon without a bottom who stole the dead sea scrolls and eventually got trapped in a snowglobe.
Ooh, the story with the squid guy was terribly dramatic, as it appeared as though he killed a bunch of characters when really he just teleported them away.
You know, I actually think I learned alot about different cultures from reading TMNT, which is really great and suits the title quite well. It's about family, wisdom over violence, doing good and accepting people, no matter their appearance. Oh and fun action of course.