A tool that provides a means of performing rapid mission studies using electric propulsion system technologies is developed to simplify the complex multidisciplinary problem of simultaneously optimizing low-thrust trajectories, propulsion, and power systems. The tool implements analytic expressions for optimized low-thrust trajectories and combines them with electric propulsion system performance and mass models. The tool then finds the maximum delivered payload mass and the corresponding optimum power and specific impulse. The tool uses existing technology as a baseline but permits tweaking technology parameters to help identify sensitivities and mission enabling technologies. Design scaling curves for technology parameters are examined. In addition, electric propulsion engine lifetime limitations are included. This identifies optimum flight times for given missions. A study for Earth-Jupiter transit is presented to demonstrate rapid system level trade studies and examination of limits in current electric propulsion technology.