To me I really like Kouji Kumeta , the creator of Sayonara Zetsubou Sensei , Joshiraku and kakushigoto, his simplistic yet very unique artstyle has really inspired my work , since i find animes with overly detailed artstyles abit off to look at (this can work , inaka isha has an extremely complex creepy animation, but its fitting for the contents .) His work is also really funny , do you know that one famous opening called the Joshiraku dance? Yeah .. HE IS THE ORIGINAL CREATOR OF THE ANIME!! I think his stuff is worth checking out , especially since its extremely underrated (abit of a warning for Zetsubou sensei , as it can get offensive and weird sometimes , the rest is good tho).
Which manga artist do you think is underrated?