[Mugen no Ken]

Best: Gokaiger could, in all honesty, if you removed the anniversary elements, stand as it's own series. Sure, you'd have to add pirate themed upgrades to fill in for the grand powers... But it's so firmly rooted into it's own concept BEFORE you hit the anniversary stuff it ends up working so vey, very well.

The past Sentai heroes end up replacing the typical victims of the day plots, but that creates an interesting thing. There ends up feeling like VERY little time is wasted. One-off episodes that don't matter in the grand scheme feel a bit less frequent than a lot of shows. And even THOSE I've enjoyed quite a bit. I don't think there's a single episode I've hated. And of course the cast, and characters. I even grew to love Walz Gil before he passed.

Hell, I could probably fill a book on what I think are all the best elements, so...

Worst: That it has to end, but, you know what they say about all good things.

Though for an actual thing, I suppose there's some weaker mech action littered through the show, though there ARE still some great mech fights.