Was Krang ever in the new series?
I always sort of wanted the Technodrome to finally get up to the surface again...
Yes, but only as a joke. You see, Krang was based on a concept from the comics, an alien race called the "Utroms," basically brain shaped creatured that have mechanical humanoid bodies. The utroms were directly responisble for the Turtles' mutation, when the wate product from their teleportation machine somehow fell into the sewers with a bunch of baby turtles.
In the episode "Secret Origens" (the last part of the saga), a bunch of Utroms, san their bodies have to crawl to their transportation device. One of them proclaims "I hate walking on my tenticles" in the familiar voice. Andother Utorm says, "Shut up, Krang".
That episode also parodied April as a news reporter (as she had to disguise as a news reporter to get close to the action), and they even made fun of her yellow jump suit ("you look great.. if you got a job hauling toxic waste")
Even Bebop and Rocksteady are mentioned at some point, but they arwen't parts of the show, as they weren't parts of the comic. The only other mutant animal in the comic book universe was Leatherhead, and he wasn't the rajin' cajun he was in the cartoon.