This paper seeks to expand our previous understanding of the electrostatic interactions between pairs of complementary electrodes on a planar self-alignment/self-assembly platform. The total electrostatic field is composed of a homogeneous field between the electrodes and the fringe fields at their edges. An analytical function is provided to quantify the force of the homogeneous field and FEM simulations provide us not only with the total electrostatic force, but also with prediction rules for its maximum value and relative displacement as a function of the selected electrode diameter. Furthermore, the limitations of the analytical approach are analysed and a comparison of the measures of homogeneous and total force is made. The results are afterwards discussed, indicating a complex system of electrostatic interaction, greatly affected by geometric as well as electric parameters that need to be taken into account for the amelioration of the platform's design and performance.