I've been a reader of One Piece on and off for years now. The premise of "uhm actually, being a pirate is about having fun with your friends" is what kept me attached. Exploring the world with your friends while dodging the grip of a UN for Monarchs is a very cool premise. It's a really romantic version of piracy. In practice though the crew's journey seems to be them going to the most dystopian fucked up islands imaginable and doing a regime change. I feel like a different formula would've been cooler. But as the current president of the United States once said, I'll still keep drinking that garbage.
It's got an amazing world though. Water 7 and Skypeia are my favorite locations.
spoiler
Critical support to the anti-imperialist Doflamingo for standing up to the World Government :fidel-cool: jk
One Piece is awesome, it's got a lot of problems but it's such a fun romp in a cool well thought out world with (generally) fun characters AND it has a lot of left wing themes. Skypeia is a personal favourite arc of mine cuz of the themes, which I never expected in an anime, not to mention it's not a super problematic portrayal.