What are the motifs in The Best of Roald Dahl by Roald Dahl?

Many of the the stories in "The Best of Roald Dahl," revolve around a bad or deceitful person getting what they deserved. In at least five of the stories, that applies to a married couple. Mary Maloney in "Lamb to the Slaughter" and Mrs. Foster in "The Way to Heaven" both orchestrate their husband's deaths as a way to get back at the men for the torment they caused their wives. William, Mary's husband is "William and Mary," is kept alive as only a brain and an eye, but Mary gets her revenge because her husband now has to watch her enjoy all the things he had previously forbidden.