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 Zeo
Anvilicious: "A Season to Remember." Rather telling when the villain's main weapon is called the "BiasBlaster." ("It will make people only see things their way!")
Characterization Marches On: Adam, Kat and especially Rocky. In MMPR, the replacements were Suspiciously Similar Substitutes who were sort of just....there to fill in spots left behind by better rangers. But now that they were original members of their own team, there was more room for them to grow as characters. Don't be mistaken, the show was still all about Tommy and their personalities were still relatively bland and undefined compared to the originals but at least now they didn't feel like just mere replacements.
What's really funny about it is that Nakia Burrise has a great singing voice. Jason David Frank... does not (although, some have said that Frank's singing voice is tolerable; he just thought it would be funnier for Tommy to be hideously off-key, which it was.)
Crowning Music of Awesome: The Zeo theme song is a beefed-up version of the original "Go, Go Power Rangers!" theme song and it is friggin' awesome.
Typically portraying her as a yandere who wrote the letter herself.
Interestingly, if you watch the series Kat's feelings are one-sided and she understands that Tommy is still pining, so despite her own wants she tries time and again to find Tommy a new love interest who ISN'T her. Eventually he realizes on his own what he's got in Kat. Word Of God even says this is intentional to keep Kat from looking like some heartless boy stealer.
The previously-mentioned Zeo theme is a definite ear worm too.
Fan Dumb: In regards to the Fanon Discontinuity about "A Season to Remember" below. A fair number oppose the future events depicted in that episode - specifically Tommy and Kat being married due to their own shipping preferences. Word Of God from multiple producers have stated that those future events are indeed canon, but opposition persists in the face of that.
Fanfic Fuel: The abandoned Zeo Zords presumably still in the holding bay...what if someone found them?
Unfortunate Implications: The crew decided to reveal that Tommy had Native American heritage at the same time he became the Red Ranger while emphasizing it in a way that basically consists of "brothers, an arrowhead, and Eldritch Abominations", with All Natives Are Lakota thrown in. Granted, Lakota myths do feature brothers taking on an Eldritch Abomination, but still...
Behind the scenes it was just an excuse to get Eric Frank a guest appearance on the show.
Villain Decay: While Zedd's marriage to Rita is argued if it is truly an example (Post "decay" Zedd having done more damage to the Rangers), Zedd and Rita being forced to travel around in a camper is a pretty solid example. Thankfully it doesn't last and by the end of the season they're no longer afraid of the Machine Empire at all and Rita manages to create a monster that beat even the Ranger's ultrazord!
Played straight with the Machine Empire. They are initially built up a a threat even greater than Rita and Zedd when they chase them off, but despite showing they have an army and also statements of conquering whole galaxies, we never see them do much besides Monster of the Week plans, which they had less success with than Zedd and Rita. Rita even lampshades this in the finale when she says their not afraid of them anymore with how that be then they've become a joke.