I think it does get a bit formulaic/repetitive around 200 chapters and still a bit moving forward. But it does get better after that. I believe it's because at around 200 chapters, cliches are still played straight. And since the foreshadowing aren't exactly unrevealed yet, it felt repetitive as they are taking more time to set the foreshadowing in place, which are quite well hidden foreshadowings.
The author worked very hard to make you believe that it is a standard series with standard settings at that point, and none of the mysteries are revealed or touched upon yet. There wasn't much character development at this point either so the characters often fell a bit flat there. When I was reading around chap 200, it already felt very end game, but to my surprise it actually wasn't. You slowly discover that the narration is actually an unreliable narrator and there are more going on. It's nice to see a lot of the things you disregarded at the beginning for being standard in this genre get flipped later on, and the pay off is great.
That's not saying this novel doesn't have a common theme (it's a nakama story and a feel good story), or that it is anything record breaking which makes you wonder about the meaning of life. But it is quite a nice and solid story to read as entertainment. Objectively, I'd give this a solid 8.5/10. It's solid, and while not ground breaking it is well self-contained. Subjectively tho, I enjoyed it 10/10. I honestly think it's worth giving it a shot again.