The goal of this work was to develop an automatic scheme for selecting active spaces for the calculation of vertical excitation energies in a predictive fashion. Towards this goal, we have presented an active space selection scheme in which active orbitals are generated by applying entropy calculations based on approximate pair coefficients to orbitals obtained by Hartree-Fock calculations and by diagonalization of a parameterized exchange-weighted operator in the space of HF virtual orbitals. By using multiple values of the parameter, we generate multiple sets of active and inactive orbitals. Then, for each of the orbital sets, we calculate a DMRG wave function, and we variationally choose among these trial wave functions the one that gives the lowest average absolute energy between the ground state and the excited state under consideration. We refer to this scheme as λAPC-tPBE, and we find that, even with only four trial wave functions, it performs robustly at selecting good active spaces for the QUESTDB database of vertical excitation energies. Furthermore, if we enlarge the trial set of wave functions to include both SA-CASSCF wave functions with small active spaces and the new DMRG wave functions with large active spaces (40 active orbitals), and we chose among them with variational selection by tPBE, we again obtain good results, even though we are now comparing quite different kinds of wave functions.