Everything Khan does in ID is to free his people, and the only times he's out for revenge is when he thinks Marcus and later Spock has killed them. Ditto Spock when Kirk dies. It's certainly not the Moby Dick theme that completely dominates Wrath of Khan.
At the start of the film we see what that the father of the little girl will kill for her. Khan kills for his people throughout. We see Kirk die for his crew. That's the dominant, recurring theme of the movie - "Is there anything you would not do for your family?"