Superman
Superman's moral standing derives from choice rather than nature. Born with godlike abilities, he consistently chooses restraint, service, and humility. The character explicitly rejects the authoritarian possibilities his power enables. His adopted humanity grounds him in the concerns of ordinary people despite his extraordinary nature. Critics occasionally note the simplicity of his moral framework, the Kansas farm boy ethics that can seem naive in morally complex situations. Yet this very simplicity provides clarity: Superman represents what humanity might aspire to become. His example inspires fictional universes' worth of lesser heroes to better conduct.
Gandalf
As a divine emissary operating under explicit celestial mandate, Gandalf's moral authority carries metaphysical weight within his universe. His role as one of the Istari specifically charges him with opposing Sauron through inspiration rather than domination, a constraint he honourably maintains despite temptation. The wisdom to refuse power, repeatedly demonstrated, establishes ethical credibility beyond mere good intentions. His judgements carry weight precisely because they come from one who has deliberately limited himself. When Gandalf pronounces moral truth, it resonates with the authority of Valinor itself. His compassion extends even to wretched Gollum, foreseeing purposes invisible to others.