Examine the role of allegory. This is perhaps the most important literary device in the play, using "Everyman" as a symbol. "Everyman" as he is called could really be anyone. He deals with temptation and must perform good deeds to repent for his earthly sins. In your thesis, address how Everyman does or does not deal with realistic issues, such as beauty, strength or wits.
Develop a thesis that deals with the morality of the story. In the end, Everyman calls out for Jesus to save him and he is called up to heaven, only to take his good deeds with him. What message does this send to the audience? How would the story be different if he was able to take another "friend," such as Beauty or Discretion with him.
Compare the play to another piece of work that has a similar message or style. For example, the allegorical story "The Pilgrim's Progress" by John Bunyan deals with a character named "Christian" and addresses how a Christian individual should behave. To form a thesis, describe how these stories are similar and different.
Consider how this play could be applied to other religions. The play is essentially a Christian sermon depicted in acts. One thesis could define how this play would be different if it were telling the story of a Muslim, Jewish or even atheist viewpoint. In your thesis, briefly suggest one or more areas where the story would be different or similar; if told to express the tenets of a different religion.
Examine the role of the anonymity of the author. There are similar works from the same era, such as the work of a Flemish play by Peter van Diest which many speculate could either be the precursor or influenced by "Everyman." How would this play be different if the background of the author could be more closely examined? In your thesis, take a stance as to whether or not knowing the author is important to grasping the message of the story.