@Tersione (For the record, I haven't read any LN / WN - I'm measuring this manwha on its own.)
Don't be a dishonest cactus-fucking shithead: That's not what I said, and you fucking know it.
"...not one of the praises I hear for this series even for the WN..." I don't acknowledge argumentem ad populam - there are a lot of manga readers (including on this website) who by their own admission don't want a complicated story. They want something where all the salient details are laid out for them and there's no need to read between the lines. Which is fine - but this isn't one of those stories. If you try to read it like that, it's going to be disappointing.
As has been stated earlier, this entire story has been filled with rather blunt hints that there is more going on behind the scenes. The monsters have not just sentience, but culture and stories of their own. The stone monsters at the beginning of the series have not been touched on since, but it was made apparent that they had a purpose and will, and probably some variant of intelligence. The dungeons connect to each other in weird and twisting ways that make it possible for a hunter to walk in, disappear, and come out many years later somewhere else. And on two separate occasions it is shown that something is manipulating these monsters, wiping and resetting them like computer programs if they step out of line.
Whether or not the manwha adequately uses these plot extensions is up for debate, and there's certainly room for them to fuck up the series. I'm not entirely happy with how monochromatically the MC interacts with the people / setting around him either: IATSK is much better at that IMO, and the MC's lack of character / competition in recent chapters certainly makes me understanding of claims of Marty Stu-dom.
But to claim that the artwork is the only major selling point is to do exactly what I've accused you of: turning your brain off.