This review is extremely biased, because, having read (and loved) the manga, I was excited for this anime from the moment I saw its first episode airing, and god damn, I was right to be excited, this is great.
What. A. Great. Adaptation. Seriously. It is beyond a faithful interpretation, the entire manga, with all its hard hitting moments are not only done justice to, they are also made so much better here!
It's not your conventional story anti-hero or power-fantasy story. A better way to describe it would be something more akin to Gesellshaft Blume. The story isn't of a man who lost everything and simply wants revenge (though Adonis does love to say so, he clearly feels otherwise and his feelings do change over time, as we can see for the first time as he passes by Vagrant town and his feelings change over time) at all cost. Nor does Adonis want to create a better world where everyone can live together. This is a tragic story. A story about a boy who had only 1 yet that was taken away from him in front of his very eyes. The story of a boy who never was allowed to have his youth or to express his anger, his sadness, his everything.
It's a very serious and touching story. Fights aren't presented as these exciting moments, but as disgusting, unfair, violent, and most of all, pointless.
It all takes place in this oh-so desolate world that was left to rot in favor of a parody of our modernity-obsessed, celebrity-worshiping societies that is brimming with creativity and tells you so much about itself without it needing to be told through dialogue. From the modern, sky-reaching towers of the capital of the Redia empire to the immaculate halls of the Nation of Witches, from the desolate feel of Sand Land and Mamuta to the lively, yet depressing reality of the Vagrant village, every location in this show is distinct and memorable, while also serving as powerful world-building tools.
All this is tied together with very simple animation (especially for any scenes including Director Shirousagi) that puts in work when it needs to (it isn't all that flashy, but it nails all the scenes that needed strong visuals (for instance, during the uses of Grande)), beautiful music (including the intro and outro songs, which I never skipped), great jokes that all land, powerful moments (episode 11's start is beyond disturbing) and wonderful characters that are given life through exceptional voice work and amazing writing.
It's finale is also done perfectly in my opinion, closing the current arc while also leaving you with enough to be excited for the future, closing with a smooth transition into the show's wonderful ending theme.

High 7. God fucking damnit, I want to re-read the manga now.