Do not have time atm to have a closer look. But have you looked into the file from Christoph to which i already pointed in the context of the group attribute statistics node.
There he has a points to faces node (as a use case for his sort node), which could be used to make the lines on each faces. By turning the faces of the pattern (which you already got as i understood) into curves and resampling it. And then play around with the group indices of that node to alter the rotations.
Not 100% sure that this works…but this is the first thing what came into my mind.