You can compare them to show the difference between an author who has meticulously planned his characters’ power escalation hundreds of chapters in advance (Hara), and an author who is quite literally making this shit up as he goes along and openly admits in interviews that he creates characters that Luffy will defeat while also having no idea how Luffy is going to beat them (Oda). Oda literally said that he had no idea how Luffy was going to beat Kaido when he introduced Kaido.
A series being fantasy or not has nothing to do with your ability to plan a characters’ development and power escalation in detail from the start. I get that OP was originally supposed to only be a 5 year manga and was artificially extended due to its popularity, but looking at a series like Kingdom, it’s clear from literal chapter 1 that Hara planned for the series to be a thousand chapter behemoth and knew exactly how the series was going to end and how he was going to get there. He literally drew Great General Shin in Chapter 1 of Kingdom so that we could see the massively epic character Shin would eventually become.
Meanwhile, I guarantee you Oda knew nothing about the power of his top tiers in early or even mid One Piece. Oda always holding back the full power of his characters might give him the appearance of someone simply saving the biggest feats for the end of the series, but the truth is that Oda has no idea what the power escalation in One Piece would look like even as far in as Marineford, where no characters showed colored Haki or Haki on the level we’re seeing now in spite of the fact that we saw top tier characters fighting at Marineford. Oda even confirmed in interviews before that he did not know how Shanks would actually fight. How do you make someone an Emperor without knowing what actually makes them strong? “Shanks is popular, I’ll make it up later!” Oda is starting to sound a lot like Toriyama who was making DBZ up week by week and had no idea what he was doing with the story.
Again, transition over to Kingdom, and we literally see the incredible full strength of a Great General in the very first war arc that we participate in. Hara knew, with exact precision, how strong his top tiers would be and how strong Shin would become, and planned this shit years in advance.
If Oda actually planned his Powerups out ahead instead of just making them up in the exact arc that he introduces them, OP would appear less of an ass pull fest being made up on the spot, and more like Oda is actually the foreshadowing genius that idiots think he is.
I have mentioned all of this about Luffy before. Luffy is the King of ass pull Powerups and Oda hands him victories he doesn’t deserve all the time. I didn’t want to repeat myself in this OP, anybody who’s followed my threads knows how hard I’ve been on Luffy the Pirate Christ lol.