The art in D.Gray-man was always great! I remember reading through it on a binge when the manga was initially on hiatus... should probably go back and re-read since that was something like 13 years ago lmao.
Manhwa:
Hey, I love me some Tower of God. The way that attacks and powers are drawn and designed is one of my favorite parts of it. Just about everything stylistically has a lore or story reason for the reason it is why it is, which is hype.
The Boxer is another great one. A sports mahwa that's fairly straightforward. There weren't any big flashy attacks, no cool crazy powers or anything of the like, but the details of the characters, the emotions conveyed in their expressions... everything about it artistically was pretty great.
Manga:
On the subject of characters, Bleach and Jojo's are top tier. Between fashion, designs of the characters themselves, and again how their powers/attacks manifest is all just top tier. Say what you want about the lack of backgrounds in Bleach, but the characters are always beautiful.
One punch man's manga is also fantastic. There's been some recent fanservicey stuff which was beautiful, but Murata has been doing a fantastic job in transforming the original sketches of ONE.
Anime:
I think when it comes to anime my favorite art showcases are the series which go a little less traditional in their approach. Things like Ping Pong, Sonny Boy, and Aku no Hana typically jump to mind. There's also the splendor that is big fight scenes provided by ufotable as they're almost always a feast for the eyes in things like Fate and Demon Slayer. And then there's the more subtle beauty in the art of some of the more 'vibey' anime like Chihayafuru, Mushi shi, Violet Evergarden, Magus Bride, and so on and so on. Anime is such a beautiful medium that it's hard to list just a few things and there's so many ways in which to divide the 'feeling' of each style and how the shows utilize it ;u;
