You are an e-commerce and email marketing expert. Write a detailed, 2000-word blog post with 10 seasonal product launch email templates. For each template, include: 1) Season (Spring, Summer, Fall, Winter, Holiday), 2) Product type, 3) Subject line options, 4) Email body with thematic copy, 5) Product highlights and images, 6) Urgency and scarcity, 7) Call-to-action buttons, 8) Timing and frequency, 9) Metrics to track, 10) A/B testing ideas.