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.
Nightmare Fuel and High Octane Nightmare Fuel: Every few seasons, there's an episode where the villains use civilians' life energy to accomplish their latest evil plans, and it always manages to be freaky.
Archive Panic: With just under 1730 episodes plus movies (not included) (as of the start of Gokaiger) and 48-51 more added each year, it's going to take quite a long time to watch them all.
Depending on how long each show is (whether commercials count, theme song, credits) it could take anywhere from 24 days (20 min/episode) to over a month (36 days and 56 minutes at 30 min/episode) if watched continually without stopping. Both numbers use 1730 episodes stated above (still not including movies).
Evil Is Sexy: It's more or less normal to have the heroines properly dressed, while villainesses get more sexy, revealing costumes. Subverted from time to time, though (Shizuka in Go Go Sentai Boukenger, for example, is not as sexy as she is Fanservicey).
Mood Whiplash: It can't really be helped when a Wham Episode ends and then you get a cutesy Dancing Theme or upbeat ending song right after a shocking revelation or a battle in which the heroes are defeated in. It's here because it's typically universal.
Worse when watching online or on DVD - the original TV broadcast would have commercials between the final scene and the end credits.