In RBFE network generation there exist two main challenges: estimating the reliability of RBFE perturbations that form the edge of a network a priori, and optimising resources allocation to process a network that spans all compounds. The current work describes research into the first problem. Investigations into optimal network topology are actively being carried out. Because the accuracy of an RBFE protocol is sensibly affected by the choice of the perturbation network this has important implications for the field. For instance, forcefield benchmarking studies with a given RBFE implementation should ideally be carried out with the same perturbation network. Benchmarking studies of different RBFE implementations should be made with networks tuned for performance for each implementation.