What signals would you use to improve Meta's News Feed relevance?

Focus on identifying specific user engagement metrics that indicate content relevance, such as click-through rates, time spent on posts, and user interactions (likes, shares, comments). Consider both explicit signals, like user preferences and feedback, and implicit signals, such as browsing behavior and content consumption patterns. Discuss how you would prioritize these signals based on their potential impact on user satisfaction and retention. Additionally, think about how to balance personalization with diversity in content to avoid echo chambers. Finally, be prepared to address potential ethical considerations in data usage and algorithm transparency.