If we look again at the peshat of the pesukim in the Megilah, perhaps another answer can be suggested. The Megilah tells us in (1:3-4):

(3) In the third year of his reign, he made a feast for all his officers and his servants; the army of Persia and Media, the nobles and princes of the provinces, being before him; (4) when he showed the riches of his glorious kingdom and the honor of his excellent majesty, many days, even a hundred and eighty days.

A simple reading implies that Achashverosh’s primary motivation in throwing the party was to show off all of his wealth and riches.  Indeed, the Megilah continues by describing all of the fine materials and utensils which were used at the second party for the people of Shushan. Perhaps this detailed description of all the king’s riches is meant to convey that the very reason for the party was simply for the king to show the people just how rich and mighty he was.

Throughout the Megilah, Achashverosh is portrayed as a man with very little self-confidence. He never makes an independent decision and is therefore easily manipulated by his ministers and members of his court. Those decrees that he does make, he often regrets later.  A person lacking self-confidence always feels the need to show or prove to others just how great and powerful he really is. As a self-conscious, non-confident king, Achashverosh felt the need  to compensate for his sense of inadequacy by displaying his wealth, hoping that his people would be led to think of him as powerful and worthy of great honor.

This midah of Achashverosh is in direct contrast to Esther. She is a beautiful woman with great faith and confidence, and because of her self-assurance, she asks for nothing from Hatach, feels no need to speak of her past, and has no need to show off her strength. Her strength is proclaimed by her silence, her modesty and her internal ko’ach (power) and emunah (faith). This is the ultimate strength of Am Yisrael: our internal power, our spiritual and inward strength, our ko’ach penimi.

In the parshiot at the end of Shemot and the beginning of Vayikra, we read of the construction and erection of the Mishkan and the service performed there. The crown jewel, the most prized of all the vessels of the Mishkan, is the Aron Kodesh with the golden Keruvim (cherubs). It is no accident that the most prized vessels remains hidden behind the parochet, to be seen only by the Kohen Gadol and only on Yom Kippur. In contrast to Achashverosh, we feel no need to publicly exhibit our riches and our greatness.  It is only those who lack real inner strength who feel the need to show their prized possessions to the world.