Good. That's your personal opinion. It still doesn't help me as you didn't specify any elements of the manga that you like.
I don't have time to elaborate on all of them, I'll hit the high notes real quick. I'll compare Hara to Oda just for comparison's sake, but really Hara is better than almost every other Mangaka in the business. Which is why he was the second highest selling mangaka of 2019 despite not having an anime adaptation at the time, unlike other Manga like OP or Kimetsu no Yaiba who bum sales from their anime adaptations instead of just being that good by their own merit.
Worldbuilding-Kingdom has the advantage of being based on actual historical events, which means the worldbuilding is extremely engaging and high quality. In a series like OP, the worldbuilding is pretty terrible because most of the islands and stories are all like separate worlds and stories that have nothing to do with each other, but in Kingdom, the world of China is heavily interconnected which adds to the sense that you are reading a living, breathing world, and not just a series of random unrelated islands all connected by their manga sharing the same title.
The Action-Kingdom has some of the most intense action scenes in manga. Whether this is in terms of 1v1 fights or grander battles. There are many reasons for this, but to list just a few: Hara is not afraid to kill off characters like Oda is, giving every action scene a real sense of extreme tension because anyone can die at any time. Hara is not afraid to have other characters shine aside from his main protagonist. Shin is rarely the one to achieve the best feats in any war that takes place, in fact I think the only war Shin actually had the best achievements in was the most recent one. This leads to other characters all getting their moments to shine and all of them having extreme hype moments instead of Shin just being a Chinese Jesus like other series like Naruto and OP. Shin has real rivals in Kingdom in Ouhon and Mouten, Luffy has cheerleaders in OP who exist to make Luffy look better. In Kingdom, Shin legit feels like he is lagging far behind his rivals
most of the time. Hara also doesn't have characters survive fatal injuries like Oda does. A character takes a fatal injury in Kingdom? Hara kills them. There is no ridiculous Pell surviving a nuke bullshit or Pound surviving Oven's glaive to the back of his head. Hara's power levels are also extremely consistent where Oda's power levels feel like Oda is suffering from dementia 30% of the time.
Story progression-Hara is not afraid to show his top tiers going all out right from the start, unlike Oda. Oda builds hype for characters by just leaving their abilities a complete mystery (lazy), Hara builds hype for characters by showing their full strength right from the start and then taking interesting plot turns with them (brilliant). Every character in Kingdom has character arcs that take place, Oda's manga is full of static characters who never go through any development. The way that Hara progresses the strength level of his characters is also much better than the way Oda does it. The way Oda makes characters stronger is just by repeatedly giving them powerups and leaving the reader to just take a random guess at how close they are to their opponents because again, Oda doesn't clarify how strong his top tiers are, leaving readers to just guess about how close Luffy is supposed to be to his opponents. Hara shows his top tiers going all out right from the start, so that when Shin, Ouhon, and Mouten receive powerups, the reader is
directly aware of how they compare to the top tiers of the manga and how close they are to reaching that level, which makes their growth and development much more rewarding instead of just completely random like it is in One Piece.
Female characters-Hara has straight up the most well developed, most badass, and most respectable female portrayal in any manga. I won't elaborate here.
This was just a general, unstructured post but the reasons why Hara dunks on Oda are numerous. It's like I said, even with Oda having an anime to increase his manga sales, and OP being in the middle of it's most hyped arc of all time, Kingdom still smashed OP in sales in 2019, we'll see what happens for 2020.
That arc alone >>>>>> Every OP arcs.
