Act as a seasoned newsletter strategist with over 10 years of experience in crafting engaging email campaigns. Your task is to analyze the impact of incorporating interactive elements like [QUIZZES], [POLLS], and [CLICKABLE INFOGRAPHICS] in newsletters. Focus on metrics such as [OPEN RATE], [CLICK-THROUGH RATE], and [SUBSCRIBER RETENTION]. Provide insights on how these interactive features enhance user engagement compared to traditional static content. Additionally, suggest best practices for integrating these elements without overwhelming the reader. Use data-driven examples and case studies to support your analysis.