Pandarus is the text is seen as lecherous and scheming, which is where the word pandering come from. Though this reputation isn't deserved. The Iliad mentions him as a well trained soldier and a noble fighter. Shakespeare got his interpretation from the works of Chaucer. Not the Iliad.
Achilles in this play is very different from the character in Homer. He actually supports the idea of peace! The Achilles of the Iliad would be disgusted by the thought.
Hector is far more viscous to his wife whom he loves very dearly in the Iliad. Interesting to note that the Iliad portrays women far more equally than Shakespeare's play.