Something that might help would be to have the grids in some sort of canonical form: as swapping rows and columns doesn't change the score, for every configurat

Something that might help would be to have the grids in some sort of canonical form: as swapping rows and columns doesn't change the score, for every configuration there is a reordering such that the whole grid value is minimal (i.e. if we read out as a 279 digit number). Intuition says that if grids were brought in such a canonical form, recombination might work better.