I was going to suggest overlaying different patters, but apparently patterns cannot be scaled or otherwise modified in any way. Would using a wave work for your case instead of a drawn pattern? You could create a 2D matrix with your desired pattern, color it accordingly and then add a sub-graph to mimic the desired pattern. For example, here is a simple way to create a diagonal pattern using a wave:
•K0 = 30; K1 = 4
•Make/D/O/N=(1001,1001) pattern = (abs(mod(p+q + K0/2, K0) - K0/2) < K1/2)Here, K0 is the distance in data points and K1 is the line thickness in data points. This approach is a bit tedious, but would avoid summoning Illustrator after each export.