Recent growth in the area of model-based product development in the automotive industry means that system models in electronic form become increasingly more available as they progressively find more applications in the course of the development process. Such models, Matlab-Simulink models for example, are currently used for simulation, fault injection and source code generation. In our work, the utility of such models is pushed further into a hitherto unexplored area that of safety and reliability analysis. We propose a design process in which techniques for semi-automatic safety and reliability analysis of such models are combined with multi-criteria optimisation techniques to assist the gradual development of designs that can meet set reliability and safety targets within pragmatic cost constraints. The proposed process relies on tools to automate some aspects of the design that we believe could be automated and thus simplified without any loss of the creative input brought in the process by designers.