Not gonna lie I went into this series fresh off the anime and had high hopes and expectations. I was sorely disappointed with what I found.

Story:

The anime strongly reminds of Magi (manga version) and so diving head first into KnY's manga, I expected some strong but compact narrative arcs. What I got felt like a cheap imitation. The arcs are compact alright, almost to the point of rushing them. Everything that happens within a set arc seems to have limited impact on what happens outside of them. Where a truly inspired series like Magi sees what happens in each arc have a definitive impact on each arc going forward (and the narrative overall), KnY struggled to keep any arc relevant after it closed. It sort of feels more like a collection of connected stories, as opposed to one complete story. This isn't an uncommon problem with shounen, but it is especially exaggerated in the case of KnY.

Art:

No complaints. It's a pretty generic world but the setting being Taisho era Japan is neat, if a little underwhelming considering how little the setting is actually utilized. Character designs are inspired though. Well done there.

Characters:

So, the early arcs of the anime and manga alike didn't bother me so much because they're there to introduce us to these characters, their past, their motivations, etc. At some point though you have to give your characters, especially your morality-driven protagonist, a real question to struggle with. Tanjirou never really questions his actions or his motives. It's all for revenge against Muzan. This renders every battle outside of the one he is sure to wage against Muzan totally moot, unless someone else is there to bridge the gap (and often there is, re: Kyojurou, Giyu, etc). Tanjirou is seriously one of the least interesting protagonists I've ever come across. He's boring. Should've made Giyu the protagonist instead of giving him a spin-off manga. Tanjirou would have made a decent side character, but he just doesn't cut it when it comes to being a main character.

Enjoyment:

Due to the lack of narrative cohesion, uninspired characters, and overall poor writing, my enjoyment of this series bottomed out after the Demon Train arc when I realized things weren't going to improve. I kept reading, just to see if I was wrong, but I've caught up with the current, final arc and I'm still not impressed.