Seeing there ar and many 10s on the manga version of Shingeki, I get quite curious and got thinking back in day I loved reading the manga and reflecting when it lost me.

So to begin with, I wanna say that people get some things wrong, the concept of a story not being "your typical shonen" is quite silly, first, because "shonen" is demography refering to young male audiance and therefore it has nothing to do with what you're usually reffering to, the right term is either battleshonen or action manga. Second, because there are plenty of "seinen" manga (that is, manga aimed to adult male audiance) from different genres that share many of the same writing flaws and rely too much on cheap shock value and gore to seem more "mature", it's just a writer choosing to tell things more suited for adults, it doesn't mean his actual skills have a power up or whatever.

It doesn't matter if you grew up reading battleshonens and got tired of some of the same tropes, it doesn't automatically makes a manga with adult themes and gore an automatic masterpiece, there're many things to take into account to judge quality beyond the shallow "I've see this trope before".

Having said that, I used to like Shingeki, mainly because of the anime adaptations, even back when I got into the manga I did like it for what it was, the world was cruel, the setting was interesting and creative, the titans were and still are quite scary and creepy, and we see the consequences of mankind greed and apathy, and that was nice.

But then as the time passed and I learnt more about art and writing and some of its flaws started getting more and more visible to me.

STORY (poor)

The story is quite messy, it had plenty of potential from the get go, but Isayama goes different places and it's clear he didn't plan everything through, his foreshadowings aren't quite actual "foreshadowings", they are more of a "I'll let this loose ends so that I may think about what to use it for later" and that wouldn't be a problem IF ONLY these loose ends were tied in a natural manner afterwards. The manga changes its genre constantly, first a survival manga, then it gets tossed aside (almost completely) to give place to a political internal dispute, then it changes itself completely in the post time skip into a rather weird and irresponsible use of sensible historical symbology that definetely doesn't fit the "there are always two sides" narrative.

Other aspects of the story also aren't properly handled, like the power system, that is completely convoluted, badly explained and with new rules taken out of the blue, some of which aren't bring up again for convenience.

There are important plot points that are closed/ solved offscreen with no impact, there are pacing problems, plotpoints always take the fallacy of false dillema route, dialogue are just bad writen there are plenty of text to read with little personality that ignores "show, don't tell" approach, etc.

Also, it gets pretty confusing to understand what's going on and what characters are talking about, people usually say that it's like that because it's too complex and that maybe things will be "explained later" or that they're a "mistery, but when this feeling is that constant it gets obvious that the author is not good a a storyteller.

It's a story that is trying to go into dark yet human territory like A Song of Ice and Fire books or Breaking Bad, but the author doesn't have the same skills tu pull it off in a deep and meaningful way.

Also, it's not the main focus of the manga, but Isayama tries it anyways: jokes.
They are awful, he is not good or clear enough for it to be funny, sometiimes they take more panels than they deserve and doesn't make me laugh once.


ART (poor)

The art is... bad. There are few shots in which I can see dinamicity, mostly with Titans and the odd artstyle really does fit with the creepiness that are Titans, I appreciate that, but most often than not there are more problems. The paneling is just terrible and uncreative, character designs aren't expressive - to people that somehow thinks that's because they are nuanced expressions, no, they just aren't clear - and it's easier to mistake a character for another, we can't see difference between characters body expressions and sillouetes, composition is messy, characters facial features and proportions are inconsistent, etc.
I can praise background art, but I wouldn't be surprised if it's an assistant that takes care of this department to be honest.

CHARACTERS (decent)

I HAVE to point this out: most characters are NOT deep or good written as people say.
How do I know that? Well, there jusn't isn't much to say about each character, pretend we have a Dnd-like paper describing each individual character traits and quirks, backstory, flaws and positives, goals and etc. There isn't much, Eren doesn't have much to be told besides being one person that want revenge (and that gets even more revengeful with a flop of a switch), Levi is edge and badass (I give him that) but that's it, Mikasa is just.. one-note really, Armin is the smart cautious one, etc.
If I were to point good examples, I'd say Erwin got a nice closure, Jean used to be the most interesting gray character and Reiner is currently the most well developed of the bunch (only after the timeskip).
But aside from them, characters in general are either gimmicky, unninteresting, annoying, and without nuance.
People are impacted for their deaths more because they are gruesome and people get shocked by the idea of getting eatting alive and whatnot, but definetly NOT because the characters have Breaking Bad/ early Game of Thrones level of characterization.
An example in a battleshonen: One Piece.
People complain about OP fake deaths, and I agree they're silly, but when the author does kill a character and wants us to feel for them, he knows how to make us feel for them and how to build up plot and move the pieces in order for it to happen. Same thing goes for HunterXHunter and Fullmetal Alchemist mangas, another examples of oftenly underestimated stories because they're ""shonen"".

ENJOYMENT (fair)

I give it a slight high score because it really works with interesting setting and concepts, it's not perfect, but it actually fun to see Titan dinamics in action, I'll give Isayama that merit.
What gripes me is that the other problems bring it down, because there's just so much lost potential.
I can only imagine what it would've been if other mangakas had their own version of Shingeki no Kyojin past chapter 1.
Imagine Kentaro Miura working on it?

OVERALL (mediocre)

It has interesting concepts and is ambitious, but like I said, being impressed by how different it is and by the fact it plays with adult and morally questionable themes that you haven't see before will only take you that far until you read other stories that have work within the same proposal, at that point, it wont really be only about being impressed by what tropes you didn't see (because eventually you'll realize nothing is 100% new), execution will matter more than what tropes are left to see, and that's why I don't think Shingeki is as great as I thought it'd be, being different wasn't enough for the problems I see along the way.