What do you see in the epic that identifies dharma?
I had to pare down the original question, but I invite you to resubmit it in separate parts. I think that the concept of dharma or actions taken to uphold the natural law that sustains being is evident in so much of Lord Rama. The epic is one that shows Lord Rama to be the embodiment of dharma. He does not deviate from upholding this natural order and his duty to it. As a son, Lord Rama follows the words of his father in ordering his banishment, regardless of how he, himself, views it. The order is flawed, motivated out of personal desire of his wife and not out of his own volition and not out of the needs of the kingdom. Yet, dharma requires that the son adhere to the wishes of the father. As a husband, he never falters in the reverence that he gives to Devi Sita and in doing what must be done in order to retrieve her from evil. The natural order in which a husband reveres his wife is evident in Lord Rama's actions towards Devi Sita. As a military leader, Lord Rama respects the natural law that views military conflict as the last possible option and does his best to minimize the loss of life of his soldiers. As a brother, he shows complete devotion the natural order in respecting both Lakshmana's being and in returning just in time so that Bharata would not set himself upon the pyre. As a Brahmin, Lord Rama's penance at Rameswaram for the killing of Ravana shows how much devotion to the natural order, or dharma, guides his actions. As a political leader, Lord Rama shows dharma in submitting to the will of his people in asking Devi Sita to walk through the fire. In these examples, dharma is embodied in Lord Rama.
At the same time, Lord Rama's examples reflect dharma in other characters in the epic. Devi Sita matches Lord Rama in adherence to dharma in how she never relents to the touch of Ravana and how she shows complete loyalty to her husband. Lakshmana adheres the dharmic conception of loyalty to brother, something that Bharata also shows even though he is in the position of political power. In placing Lord Rama's slippers on his head and then on the throne with a vow to self- immolate if Lord Rama does not return, dharma is represented. Dasaratha reflects dharma in recognizing the intrinsic injustice in his command to Lord Rama, dying of a broken heart as a result of violating the natural order of being. Even Mandodari recognizes dharma in her consistent pleadings with Ravana to change his ways and her defense of Sita, while Vibhishana shows an adherence to dharma in standing against his brother who is violating this natural order.