If we examine the Iliad, there are a few key figures. Achilles is the main figure. If we sketch his character, we can say that military prowess, pride, and wrath characterize him. When Agamemnon slights him, Achilles holds a grudge and cannot be moved. Even when the Trojans begin to take the upper hand, which means Greeks are dying, he won't go back into battle. His wrath towards Agamemnon is too great. The same characteristic emerges when he kills Hector and won't allow his body to be buried. In many ways, the Iliad should really be called the wrath of Achilles.
A contrasting figure is Odysseus. Odysseus is a different type of man and leader. He is characterized by cunning and smooth talking. He is the one who is able to think outside the box. This is why he is the one who is sent to woo Achilles or to smooth things over. And even within the Trojan war stories, he is the one who made the great artifice of the wooden horse.
If we compare the two men, we see two different types of heroes. One is characterized by military prowess, wrath, and pride. The other hero is characterized by cunning. Both are heroes, both are Greeks, both are leaders, and both are very different. Also they both get an epic dedicated to them.