1. A neurostimulation system comprising: a neurostimulator configured to deliver electrical stimulation energy via a plurality of electrodes; and controller circuitry configured to: define a set of stimulation parameters for the plurality of electrodes as a function of independent contributions of a physical electrode parameter and an electrical source parameter for each electrode in the plurality electrodes; and instruct the neurostimulator to deliver the electrical stimulation energy based on the defined set of stimulation parameters.