I agree with you on the episode structure. It's only half a teamwork episode, it seems to get interrupted by the power up and derailed as Takaharu then defeats the monster almost entirely by himself with a last ditch effort to include the others...which isn't even initiated by him meaning he didn't learn the lesson. Not a fan of the power-up, it's too boxy and reminds me more of a samurai. I'd expect a ninja themed power-up to be more streamlined. I think Takaharu still sees the other Ninninger as rivals for the Last Ninja rather then teammates. You could blame that on their grandfather for making this fight against evil a competition, but Takaharu is still an idiot.