Absolutely.
I mean, if there's any things that I take issue with in the original 80's series it's the crap half of episodes of season 3 that were clearly rushed out and have the same "Krang and Shredder try to get alien artifact from obnoxious aliens" plot, the European Vacation arc, Lord Dregg, and the fact that Casey Jones and Usagi Yojimbo were painfully under utilized.
And I get that the 80's series was sponsored by a toy company and made as an excuse to sell toys. That of course lead to a lot of episodes about toy related mutants. Though this usually lead to them being underused (Mona Lisa and Mondo Gecko especially), or being shoehorned in with a terrible premise (Ray Fillet and Wingnut and Screwloose). It would have been great to see Casey Jones running around as a vigilante or Mondo Gecko being a close ally of the turtles, but they filled those gaps with meh characters exclusive to the show we didn't need. Heck, the comic book existent Triceratons made one puny appearance in one episode and were never heard from or seen again even when the show took place off world with Dregg. Heck, they could have used the Triceratons in his stead.
Usagi was used in 2 episodes and never seen again, much like Casey had 3 episodes and nothing. I find it hilarious that the current Nick series has done more with Mona Lisa as a space warrior than the original did as a companion to Raph. And I still find the Ray Fillet and Wingnut and Screwloose episodes utterly unwatchable. Archie did much better with those characters and then some. Ray was a pointless sidekick to a fish themed mad scientist, Wingnut and Screwloose were alien army men. Though I do find the Batman and Robin standins an improvement (and their Nick episode was a similar, but darker version of Chin Up from Nick's other show, FOP), I kinda wish they went for the Archie origin of being victims of Krang's armies taking their planet (which was at least name-checked in Nick's cartoon). Of course, I also liked Leatherhead's archie origin, but loved that the Nick origin was a dark version of his comic book/2k3 story. That is, instead of Utroms helping and raising him, the Kraang mutated him and used him for experimentation.