Family-Unfriendly Aesop: Carranger vs Ohranger has Kyousuke learn an important lesson, that he should always judge whether someone's good or not based on their physical appearance.
Hollywood Pudgy: Youko. A big deal is made in episode 11 about how overweight she is with everyone from the monster of the week to news reporters commending on it. When she is shown in a bikini, however, she is basically skin and bones.
Not just that, but the "car" theme was already used by Kousoku Sentai Turboranger, something that was referred to even back when Carranger first came out (and Gokaiger doesn't hesitate to use for a gag). Ironically, the full title of this series was originally the preliminary title for Turboranger.
It's also similar to Blazing Saddles in that it's a comedy involving an army of thugs sent to clear out a small backwater to make way for the construction of a lucrative transport route.
Tear Jerker: The death of Speed King Max in episode 9 is not played for laughs at all, and it's heartbreaking.
Win Back the Crowd: After fourprecedingseasons of mixed audience reactions and wildly varying styles, a bit of parody restored viewer faith. Helps that it does the parody right - everything is ramped Up to Eleven, both good and bad. The serious moments are serious, the comedy moments are hilarious.