Design a comprehensive microservices architecture for a global e-commerce platform expected to handle 100,000 concurrent users during peak sales events. Your solution must address the following requirements: 1) Decoupling of product catalog, user management, order processing, and payment gateway services. 2) Implementation of an event-driven communication pattern using a message broker like Kafka or RabbitMQ. 3) A strategy for data consistency across distributed databases, specifically handling eventual consistency for the inventory service. 4) Auto-scaling policies for container orchestration via Kubernetes to handle traffic spikes. 5) A detailed circuit breaker pattern implementation to prevent cascading failures. Provide a high-level diagram description and a justification for your technology stack choices.