One of the biggest strengths of One Piece is the incredible group dynamic of the Straw Hats. So what does Oda do? He tears the crew apart and leaves Luffy on his own!

After a crushing defeat at Saboady Archipelago, Luffy finds himself soaring through the skies for several days on end. Finally, he lands on Amazon Lily, an island populated entirely by women in the Calm Belt. Can our favorite Straw Hatted pirate find a way back to his crew without any of their help?
I love Luffy’s characterization in this arc. At practically every turn in this arc, he is confronted by the reality that he doesn’t have his crew. He acknowledges that he can’t get very far on the sea without Nami, that he can’t do anything for food without Sanji, and that he has to be careful not to get hurt or sick since Chopper isn’t around to heal him. I also love how he says everything out loud to himself rather than silently thinking it; it’s an extremely subtle and fun way to communicate that he’s a man of action rather than contemplation.
Also, the fact that Luffy’s dick is made of rubber is actually utilized in the story here. Because Oda may be a genius, but he’s also completely insane. God bless him for it.
Amazon Lily itself is… well, it’s fine. We get a fine idea of the island’s culture and customs over the course of the arc. But it doesn’t have any of the ‘wow’ factor that made settings like Water Seven or Alabasta memorable. It feels like a standard One Piece island. Not terrible by any means, but not especially interesting.
The islands denizens fall into the same category. Luffy doesn’t make many friends while he’s here, but the few that he does aren’t especially memorable in the grand scheme of things. The only reason we care that they’re in danger later on is because Luffy cares. Which… of course Luffy cares. It’s Luffy! On their own, the inhabitants of Amazon Lily just aren’t all that interesting.
With one exception. And you all know who I mean.

Boa Hancock is among my all-time favorite One Piece characters. I love how she comes across as cruel and callous without being straight-up sinister. She simply does what she wants and anyone who gets in her way deserves to be kicked aside. She commands respect and fear not just because of her beauty and the power of her Devil Fruit that makes said beauty so deadly, but also because of her raw physical power. People tend to forget that she has all three flavors of Haki and is adept at using them. Of all the Seven Warlords, the only ones who could actually match her in power are Mihawk and Doflamingo, and maybe Blackbeard (at least at this point in the story).
I adore her chemistry with Luffy. She looks down on him because of her traumatic experiences with men and tries to prove that he’s as shallow and selfish as the rest. Yet he proves her wrong at every turn just by being himself. Her falling in love with Luffy is organically worked into the story; it makes perfect sense that she would fall for him, despite his… Luffy-ness.
The ending of this arc is also fantastic. It isn’t anything bombastic or dramatic, like, say, the defeat of Crocodile in Alabasta or the farewell to Merry in Enies Lobby. But it’s a powerful twist that takes the story in completely different directions. The reunion with the Straw Hats will have to wait. First up: Luffy needs to save his brother.
A wonderful twist that takes the story directly into two of the greatest arcs it will ever have.
Amazon Lily is an incredibly simple and short arc, but a remarkably effective one. It introduces an incredible new character in Boa Hancock, sets the stage for the following two arcs perfectly, and makes full effective use of the Straw Hats being divided. It is a fantastic final moment of calm before the biggest storm the series has seen up to this point.
Buckle up, everyone. Cause shit is gonna get crazy.