Current systems engineering efforts are increasingly driven by trade-offs and limitations imposed by multiple factors: Growing product complexity as well as stricter regulatory requirements in domains such as automotive or aviation necessitate advanced design and development methods. At the core of these influencing factors lies a consideration of competing non-functional concerns, such as safety and reliability, performance, and the fulfillment of quality requirements. In an attempt to cope with these aspects, incremental evolution of model-based engineering practice has produced heterogeneous tool environments without proper integration and exchange of design artifacts. In order to overcome these shortcomings of current engineering practice, we propose a holistic, model-based architecture and analysis framework for seamless design, analysis, and evolution of integrated system models. We describe how heterogeneous domain-specific modeling languages can be embedded into a common general-purpose model in order to facilitate the integration between previously disjoint design artifacts. A case study demonstrates the suitability of this methodology for the design of a safety-critical embedded system, a hypothetical gas heating, with respect to reliability engineering and further quality assurance activities.