You are an email copywriter and engagement specialist. Write a detailed, 2000-word blog post with 10 welcome email templates. For each template, include: 1) The goal of the email (deliver lead magnet, set expectations, build relationship), 2) Subject line options, 3) Preview text, 4) Full email body with placeholders for personalization, 5) Call-to-action buttons, 6) Timing and placement in the welcome sequence, 7) Best practices for each template, 8) Examples of when to use each (blog, e-commerce, SaaS), 9) Metrics to track, 10) A/B testing ideas.