These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Power Rangers Ninja Storm
Ass Pull: The writers were very forthright that the last four episodes of the season (drawing many seemingly insignificant plot threads together) were rewritten in response to fan bitching. Though the precise mechanics of Lothor's Evil Plan do fall close to a Gambit Roulette of the highest order, the little details don't work and it's clearly a retcon. (Most of) The fans don't seem to care, making this a fine example of Author's Saving Throw.
Ensemble Darkhorse: While Tori was in the "Once a Ranger" episode, the real Darkhorse is Cam. Cam, the Adorkable, snarky Ranger who you sympathised with the first half of the season. The probable reason he didn't show up for that episode was because they already had two greens in the team (Bridge and Xander, the first having gotten promotion to red ranger status), and bringing back another would be redundant. Tori probably came back to fulfill Two Girls to a Team and/or to have just one member of the Once A Ranger team's Sentai counterpart be the same.
Informed Wrongness: Dustin in "Tongue and Cheek". He does develop some Acquired Situational Narcissism, but he gets chewed out well-before then (which could explain why he would let the fame go to his head). And the one character really letting him have it is Shane, who later admits he was being jealous.