The phrase "artful piece" refers to a work of art that has been carefully and skillfully created. It implies that the art demonstrates imagination, creativity, and mastery in its execution. Full definition
The pic is in the vein of an Alfred Hitchcock suspense thriller, but it's a decidedly artful piece of work. (collider.com)
The Gravedigger's Brawl is not only a very masterful work of erotica — especially in the realm of LGBT literature — but it is an incredibly artful piece of ghost literature. (goodereader.com)
To the writer's point, 12 Years a Slave is an aesthetically gorgeous and artful piece of work. (slantmagazine.com)