A system, method, and software program for facilitating the assignment of cell specifications to a plurality of cells of a system design. The methods include generating a plurality of candidate cell specifications that meet the specification for the system design. In one embodiment, the method entails using information related to intra-range preference for cell specifications to generate a set of alternative system pareto-optimal solutions which define a boundary of a region of candidate cell specifications. In another embodiment, the method entails generating a substantially uniform set of candidate cell specifications using a prediction-based performance model, such as support vector regression model or cluster-weighted model, an optimizing algorithm such as conjugate-gradient or Markov Chain Monte Carlo Method, and a sample density model. The method may also include graphically displaying substantially uniformly distributed cell performance data and corresponding system performance data, and allowing a user to focus on regions-of-interest via a selectable range graphic feature.