Gomatam Madhavachariar in a discourse narrates the symbolism
in the characters in the Ramayana in The Hindu:
Ravana is a demon with ten heads. The ten heads symbolically indicate ten indriyas. That is, ten faculties that we have, like speaking, walking, seeing, tasting, smelling etc. And these faculties are associated with the five elements.
There are three categories of qualities — sattva, rajas and tamas. Vibhishana embodies sattva — goodness. Ravana, with his anger and passion, embodies rajasic qualities. Kumbakarna given to excessive sleeping and eating and lethargy is the embodiment of tamasic qualities.
Surpanakha is illustrative of the role of illusion in inciting us to do the wrong things.
Sita can be compared to the jivatma and Rama to the Paramatma. As long as a jivatma thinks of the Paramatma, it knows no sorrow. But the moment it lets its thoughts wander in other directions, it experiences sorrow.
Valmiki talks more about Rama than about Sita, after the two have separated. That is because the Supreme One is sorrowful when a jivatma is far away from Him and wants the jivatma to come close to Him.
Hanuman is like an Acharya who brings the jivatma close to the Paramatma for, he takes steps to unite Sita and Rama. Hanuman is humble, like all good preceptors.