What are the top 10 outbound email sequencing tools available today, and how do they compare in terms of key capabilities such as multi-step email automation, personalization depth using dynamic fields and AI, deliverability and inbox safety features, integration with CRM and sales engagement platforms, analytics and performance tracking (opens, replies, conversions), A/B testing and optimization, multi-channel sequencing (email, calls, social), ease of use, scalability for startups to enterprise teams, and overall effectiveness in improving outreach efficiency, response rates, and pipeline generation?