As a final remark we would like to emphasize that the new excitation generation for singles and the improved sampling combination of doubles can also be applied to methods such as selected-CI or FCI-FRI. When combined with those methods, localized orbital bases mainly benefit from the new weighting scheme for single excitations, and the ratio of particles to empty orbitals determines whether fully-or fast-weighted particle-or holeselection is to be preferred. However, some differences between FCIQMC and FCI-FRI are to be expected; for example, the number of empty orbitals where fully-weighted hole-selection becomes better than fast-weighted for a given system might differ for the two approaches.