I think by rewatching the episode I did have a few problems, barring it going into an extra episode. The following were in my mind:
1. Why not open with all the Turtles in a trap and go back and forth between flashback and the actual events leading up to Splinter saving the day? Spectacular Spider-Man did this before with the episode called
Subtext, going between the origin of Molten Man and the current time with Spidey trying to save everyone from what MM did. I won't spoil it if anyone never saw the episode, just because it felt like Raph bashing again in this series.
2. I'm grateful that Splinter saved Karai, it's how I wanted to end this mind control arc to see father save daughter. Even with Karai controlled, why couldn't Splinter use emotion, like a hug or something similar to Raph and Mikey in the Invasion. Or, do something like the Dark Raph episode with freeing everyone barring Slash? The healing hands I'm happy for a payoff, but it feels a bit of a cop out yet again.
Probably just grasping to find flaws, but I still feel there's some mispotential in the episode.