Although the narrator doesn't technically consider Jehoash of Israel a "good" king, Jehoash doesn't do things that are totally bad. At least, he's good enough to lament the death of Elisha, and to receive prophecies and advice from Elisha as well.
In particular, at Elisha's instruction, he shoots an arrow out of the window of the room where Elisha is dying—Elisha says that it symbolizes the victory of Israel over the Arameans. However, when Elisha tells Jehoash to strike the floor with his arrows, he only strikes three times. If he had struck five or six times, he would've defeated the Arameans that many times. As it is, he only gets a total of three great victories over them.
He also helps put the cocky King of Judah, Amaziah, in his place. He compares Amaziah to a thornbush, whereas he himself is a cedar. He tells Amaziah not to start anything, but when Amaziah does, Jehoash destroys his army and captures him.