One of the major differences between Wart and Odysseus is in their tragic flaw. Odysseus is incredibly confident and impatient and almost always willing to get himself and his crew into trouble for his own pride. This weakness leads them into the cave of the Cyclops and other bad situations that end in the deaths of many of his crew and further years being added on to their journey home.
Wart's major flaw is his innocence and his willingness to believe in the good of people around him, to always assume that people mean well or are good hearted. Because of this, he is unable to recognize the evil intentions of people around him including Lancelot and Guinevere, evil or faults that will eventually destroy everything that Arthur works for and builds in the kingdom.