Leveraging partial reconfiguration (PR) can improve system flexibility, cost, and performance/power/area tradeoffs over non-PR functionally-equivalent systems, however, realizing these benefits is challenging, time-consuming, and PR must be considered early during application design to reduce design exploration time and improve system quality. To facilitate realizing these benefits, we present an application design framework and an abstract modeling language for PR (PRML). By applying extensive PRML modeling guidelines to a complex arithmetic core, we show PRML's potential for efficient PR capability analysis, enabling designers to determine Pareto optimal systems during application formulation based on designer-specified area and performance metrics.