Government and enterprise applications increasingly depend on cloud platforms for elasticity, rapid service delivery, analytics and digital integration, yet mission-critical workloads cannot be optimized through a simple public-cloud-first migration. They require deliberate placement across private, public, sovereign and on-premise environments according to service-level objectives, data sensitivity, latency, dependency and recovery requirements. This review examines how hybrid cloud architecture can be optimized for mission-critical applications in Saudi Arabia. It synthesizes literature on multi-cloud orchestration, workload portability, containerized resource management, observability, cybersecurity and resilience, and interprets these findings against Saudi Cloud First policy, Digital Government Authority guidance, Communications, Space and Technology Commission regulations, National Cybersecurity Authority controls and Vision 2030 priorities. The analysis finds that hybrid cloud value depends less on the number of connected platforms than on unified policy, application-aware placement, automated orchestration, end-to-end observability and tested continuity. A Saudi-oriented reference model is proposed in which governance and data classification drive placement decisions, while cloud-native portability, automation and resilience controls sustain service continuity. The review concludes that hybrid cloud can support Vision 2030 digital-government and enterprise goals when architecture is treated as a governed operating model rather than a collection of disconnected infrastructures.