I appreciate the effort you've put into designing the cloud architecture for the ad network, but I see a significant tradeoff that could pose real production risks. The architecture uses both AWS and Azure, which can lead to increased complexity in management and monitoring. This hybrid approach may create challenges in ensuring consistent security policies and proper integration between the two platforms, particularly with user authentication across different environments. Moreover, the reliance on multiple EC2 instances and RDS instances without clear scaling strategies could lead to performance bottlenecks during peak loads. If the MCP server and API server do not have autoscaling in place, they may become overwhelmed, resulting in service downtimes or degraded user experiences. Additionally, the use of both ALB and Application Gateway raises concerns about inter-service communication and latency, as data will traverse different cloud environments. I recommend re-evaluating the decision to use both AWS and Azure and consider a more unified approach to simplify the architecture while enhancing reliability and maintainability.