Emerging design concepts such as miniaturisation, modularity, and standardisation, have contributed to the rapid development of small and inexpensive platforms, particularly CubeSats. This has been stimulating an upcoming revolution in space design and development, leading satellites into the era of "smaller, faster, and cheaper New Space". However, the traditional requirement-centric design methodologies focus on large, complex, and customised systems. The associated labour-intensive development and production process typically spends considerable time and money on the integration and testing. This does not inherently fit with the innovative modular, standardised concepts, and the incorporation of mass-produced technologies that newer and smaller satellite classes are considering. Therefore, there is a significant potential benefit in establishing and adopting a new design architecture to effectively solve the problems rooted in the traditional methodologies and deliver innovative capabilities. This research presents a new categorisation, characterisation, and value-centric design architecture to address this need in both traditional and novel system designs. Based on the categorisation of system configurations, a characterisation of space systems is proposed, comprised of the degree of duplication, fractionation, and derivation. The three primary characteristics capture the overall configuration features, thus potential hybrid designs are promoted to improve performance or reduce cost. With the formulation of this characterisation, a value-centric design architecture for the design and development of a wide range of space systems is established. This architecture enables the use of both traditional and innovative technologies, acting as a systematic guideline for quantitative system design and analysis. The function of the design space is to integrate the cost or intrinsic properties, e.g., mass, reliability, and orbit, from subsystem level to system level, based on configuration designs. Through applying appropriate value models, these properties can be measured in the singular monetary dimension. Different properties can be used for the cost modelling of different lifecycle phases of a space system, e.g., development, launch, operation, and retirement phases. The sum of the costs of these four lifecycle phases, i.e., development, launch, replenishment, and disposal costs, can be further applied as the comprehensive objective function to enable an optimization process of design configurations to minimise the entire lifecycle costs. Thus, different system properties or design requirements can be converted into a standardised dimension, solving the design selection problems by turning the multi-objective optimization into the single-objective optimization. This design architecture embraces the innovative design concepts of modularity and standardisation, and the use of commercial off-the-shelf (COTS) products. In this condition, the design and optimization of system configurations are realised through the design and optimization of the combination and permutation of standard subsystems or COTS products. Therefore, lowering the difficulties and decoupling the requirements in designing space systems. Meanwhile, this architecture is also applicable to the spacecraft design using traditional design concepts.