>>9396960Raph being the leader was done to make him butt heads with Leo. It was clearly a conscious decision to free up Leo's character from his usual responsibilities while allowing him to compete with Raph to prove his worth as the eventual leader (which he ended up being in the end).
Splinter is a couch potato because he wants the turtles to avoid trouble but it's clear that he still trains the turtles and even disciplines them when they get into shit.
Shredder is still Oroku Saki, I don't know what you're talking about? Karai is still his daughter here and he even ends up killing her. Saki's soul was simply corrupted through lust for power under the influence of his enchanted armor, which actually recalls the Tengu Shredder from 2003 at the end of that show's life. It basically gave us a more comprehensive version of the Tengu Shredder from the '03 show.
Maybe the show was too experimental for something that's meant to sell a brand by a corporation, but it's clear that creators did their homework since many of the changes they made were either homages to previous iterations of the characters (Tengu Shredder, Utrom lore being linked with Krang, Hamato Yoshi being Splinter all along) or one that's done to spice up the usual dynamic of the turtles that we're used to.
I'm happy that it got made anyway, plus it ran long enough to actually tell the story it wanted to tell. Ironically, cutting it early feels like it didn't overstay its welcome either.