The myths in books 4 and 6 of Metamorphoses explore the role of women in myth. Arachne, Pallas and Philomela all use the art of weaving to communicate in some way. Arachne and Pallas use it to compete, however each weaves a tapestry that tells a story. When Philomela's tounge is cut out and she can no longer speak she weaves the story of her rape so that she can tell her sister what happened. We have discussed the use of "feminine arts" as means of communication and manipulation/power for women and that is true in Metamorphoses as well.
Overall, I would not say that women are portrayed in a positive light in these myths. Salmacis cannot control her lust for Hermaphroditus and she attacks him. Pallas cannot control her anger toward Arachne when she claims that Pallas did not teach her to weave and so she turns her into a spider. Niobe is jealous that people worship Latona and not her and she is punished with the death of her children and husband. Instead of taking revenge against her husband after he raped Philomela, Pronce kills her own son and feeds him to her husband. The women who are portrayed in these myths display a lack of control in love and in anger.