David Mack's Kabuki is one of the gold standards of story telling through art. Harrow County is a beautiful watercolor comic, and I'm sure you've already gotten Mignola recommended. Moebius has fantastic use of color and geometric shapes. And Kerascoet is (are?) one of my favorite creators period.
For more obscure stuff, I liked Little Red Wolf, anything by Foo swee Chin, Scurry... Uh, Meg Park, Camilla d'errico, Mall, David Petersen, Arthur De Pin (but only March of the Crabs really), Michel Gagne... Those are most of the ones that spring to mind or I have prints of. I'd have to go through my shelves to get more.