I think this show dedicated mainly for the art, leaving other part weak.
Although the art is excellent, the story & character is meh, if you care about the story you will be disappointed, it's very mediocre. Oh yes, i must mention this show have so many still shot (looks great for background art drawing, but maybe not good for animated show). As i said earlier this show is about the art of drawing, the beauty of the world, and the joy of doing work for someone.
Personally i'm very enjoyed watching this, i love art, this is very beautiful. The OP & ED is very nice, also i love the character design.
This show not for everyone, if you looking for beautiful art, come watch. But if you care about story & character, you will bit disappointed. Because the story & character is following the art direction (usually the art that follow character & story).