Been reading it lately, and it helps reduce my scrolling time. I've hardly read any, so you can recommend really popular stuff, too.
I've read Vagabond, 20th Century Boys, Claymore (years ago), and some berserk. I just finished reading Teppu, which I thought was an interesting subversion of a lot of anime tropes. I also liked that it was a short run (only 8 volumes). I guess I like seinen, but I've also enjoyed josei like She Loves to Cook, and She Loves to Eat.
Anyway, no shonen please. Hard mode: please nothing about high school
You might like The Girl From the Other Side: Siúil, a Rún. I quite liked it and I especially loved the art style.
Also I’m always raving about the Princess Jellyfish anime but the manga is even better and has a lot more content.
The art looks very nice