I was really looking forward to being able to talk about this saga, this is widely considered to be one of the first big "One Piece killers" and it's where a lot of people first dropped the series, so I really wanted to form my own opinion and talk about it.
Jaya
Jaya is a similar arc to Lougetown, it's mainly dedicated to world-building and setting up future events. It introduces Blackbeard and other Warlords of the sea. It makes it very clear how far Luffy's come since the start of the series and I consider that sense of growth really valuable, it's one of the most rewarding parts of engaging with any long story.
The most exciting thing for me is getting to see Nico Robin join the crew, who pretty much demanded that she join in exchange for Luffy forcibly saving her life. And to be honest, I did look it up, and it seems like she was the only main character who wasn't planned super early on, who is replacing this tiny little guy with plant powers. Now, I do think this was a much better call because she brings some much needed maturity to this group of teenage and young adult pirates.
When I was growing up, I had this phase where I was really into "female anti-hero trauma babies", to put it one way, some examples being Viconia DeVir from Baldur's Gate or Sylvanas Windrunner from World of Warcraft. So, I wouldn't be surprised if she ended up becoming my favourite.
There's not much else to say here, it serves as a nice breather and I guess that's fine.
Skypiea
So, a complaint that I had about the last saga was I felt that it lacked momentum, but I'd say Skypeia is a step up. Even in the beginning we see the dangers of Sky Island, and we meet the Shandorians as it culminates into a battle against Enel.
I do think he's another good villain - he does look a bit distracting, my first thought being that he looks like Eminem, but I'd consider that a good thing in this case. There are times when a sense of humour is allowed and this is one of them.
Alright, so let's talk about it, Skypiea is a controversial portion of One Piece. It seems like the majority of the fanbase doesn't like it and... I don't understand why? I thought it was a good time! I thought the location was super interesting, it changes up the formula here and there, and we get a pretty good villain. So, what's there to complain about?
The general consensus seems to be that Skypeia "feels like filler", meaning that it feels disconnected from the story and it's a little too self-contained.
I'm not sure if I'd agree. It's clear that there was a lot of work put into fleshing out the history of Skypeia, as it delves into themes of colonialism. A lot of these things tap into the Void Century, a hidden away piece of history that was erased by the world government.
This was Nico Robin's first showcase as a Straw Hat and this setting was also perfectly suited for that, as the crew's new archaeologist. And I liked the interactions between all of the crew just in general, particularly the early pairing of Luffy, Usopp, and Sanji.
You could argue that Alabasta had higher highs, but Skypiea I would argue is more consistent. It didn't really bore me and the fight between Luffy and Enel put a big, dumb smile on my face.
Skypeia isn't perfect - there was a flashback right smack in the middle of the final blow on Enel, and none of the henchmen are all that memorable, but I'd still argue that Skypeia is one of the most cleanly executed parts of the series thus far.