We envision that the present methodology of training potential energy surfaces on relaxation trajectories of solid solutions will be of high relevance beyond calculation of vibrational free energy. For example, if representative disordered structures with thousands of atoms are constructed from Monte Carlo simulations with a CE, the trained force field can be used to relax these structures, and to calculate their elastic constants, vibrational spectra and many other properties that require access to forces and stresses of structures beyond the reach of DFT. This will allow one to combine some of the benefits of on-lattice models such as the cluster expansion with the benefits of off-lattice models .