Anti-Climax Boss: At the end, Kaiser Buldont and Multiwa don't fare too much better than the usual monster-of-the-day.
Big Lipped Alligator Moment: Juri and Momo hold a dance aerobics class...for Ohranger-Robo (piloted by OhGreen and OhBlue) and Red Boxer (piloted by OhRed). They claim it's to make sure Ohranger-Robo's been fully repaired after having been heavily damaged several episodes prior, but it's still really weird.
Crazy Awesome: Gunmazin. His idea of saving a dog from a collapsing building is to restore the building.
Crowning Music of Awesome: Action! Ohranger and Niji Iro Crystal Sky. The latter was so much so that it was used as an instrumental in this series's tribute episode of Gokaiger instead of an instrumental of the opening.
Its phenomenal toy sales (also an argument for why OhBlocker was introduced) also helped it a lot.
Game Breaker: King Pyramidder Battle Formation and it's Super Legend Beam, quite possibly the most overpowered mecha combination in the whole forty year franchise! Even the Final Boss didn't stand a chance.
Hilarious in Hindsight: The Oh in Ohranger comes from UAOH, although 'oh' in Japanese can mean 'king'. Then they get a Sixth Ranger that actually has the kanji for 'oh' on his helmet, and what do they call him? Kingranger. Some of you may remember the fansub debacle from Tokumei Sentai Go-Busters, where translating GoBuster-Oh as Go-Buster King forced them to translate the actual GoBuster King as Go-Buster Oh.
Meta Mecha: King Pyramider Battle Formation with Oh Blocker.
King Pyramidder can combine with Ohranger Robo and Red Puncher, or just with Oh Blocker...but it will still have Red Puncher's gatlings on its' shoulders.
After Bacchshund is destroyed, the next monster reuses part of his death explosion...which is pretty noticeable since the set suddenly changes from mountains to a destroyed city.
Villain Decay: A side effect of the show becoming Lighter and Softer, the Baranoia Empire, which start the show with a full fledged invasion of Japan, complete with troops, artillery, and aircraft (The first episode is even called "Invasion! 1999"), abandon their initial plan to bomb Japan and its government into submission after the first few episodes. Afterwards, they soon settle into pettier Monster of the Week style schemes. Their attitude also gradually changes from sadistic Social Darwinist to more comical. In earlier episodes, Bacchus had no qualms about destroying minions whenever they displayed any sign of weakness or sympathy towards humanity. In a later episode, he and his son are seen admiring pictures of human women in swimsuits, which they subsequently try to hide from Hysteria.
Vindicated by History: While the show's been known as "The one that almost killed Super Sentai", it's gotten more favorable response over the years.
What an Idiot: Juri falls for some obviously evil traps simply because it involved cute and or fun things.
When sympathetic monster Bara Revenger is controlled by Baranoia and made to attack the Ohrangers, they have no choice but to destroy him. Nobody even brings up the possibility of instead trying to shoot the huge control box sticking out of him.