Thank you so much! Considering pitch is a great idea. For example, if we consider pitch, we could write sequences of intervals: starting from a simple unison for the first row, we can have two octaves for the second row, a sequence with two fifths for the third row, with the perfect fourth (4/3) and major sixth (5/3) on the fourth column. This would remind of a progressive 'enrichment' of harmony. However, we should neglect the extreme elements of each row, because the ratios would be too small, and we should consider modulo one octave for the elements whose ratio would be larger than 2.