A user request for a set of images is received via a graphical user interface, the subset of images having an initial order. A subset of neighboring images is selected, wherein the subset of neighboring images is ordered according to a first sequence. A first concordance value characterizing visual detectability of one or more illicit content features across images in the subset of neighboring images ordered according to the first sequence is computed. A second concordance value characterizing visual detectability of one or more illicit content features across images in the subset of neighboring images ordered according to a second sequence is computed. Responsive to a difference between the second concordance value and the first concordance value satisfying a predetermined condition, the subset of neighboring images is rearranged according to the second sequence. The previous steps are repeated for a plurality of additional subsets of neighboring images until each image of the set of images has been selected at least once as part of selected subsets of neighboring images to obtain a modified order of the set of images. The graphical user interface is caused to be modified to present the set of images on a grid according to the modified order.