What are some common recurring themes explored in superhero comics beyond simple good vs. evil?

Beyond simple good vs. evil, superhero comics frequently explore complex themes such as morality and ethics (e.g., vigilante justice vs. law), identity and alter egos (e.g., the struggle between hero and civilian life), social justice and inequality (e.g., X-Men as an allegory for discrimination), power and responsibility (e.g., Spider-Man's motto), sacrifice, loss, and the nature of humanity, often reflecting contemporary societal issues.