Harmonic Structure Import & Export:
It's good to be able to save and recall presets, but would be nice to be able to export those points as a CSV by right clicking on the graph, and similarly importing them back in from a CSV too.
Harmonic Structure Enhanced Randomisation:
If I click on the random button it randomizes all ratio points, but I would like to be able to randomize only the select points in the chart. We can select groups of nodes, but not do anything with them.
Harmonic Structure Node Locking:
Kind of inline with the above, it would be nice to be able to lock a ratio node from being edited, a little lock next to the ratio in the upper manu would be enough for this I think.
More Slots in Structure Grid:
Would be interesting to be able to have more slots available other than the current ABCD. Perhaps if there were 8 we could explore a 3D grid with X, Y and Z parameters. Or 9 for a 2D 3x3 grid.
Output Graph:
It might be quite tricky to do, but it would be nice to see an output graph like a lot of the other filters have now.
Harmonic Pan:
Width is useful, but it could be interesting to pan some of these points around.
Filter Types:
No idea if this would be possible or evern worthwile, but could be pretty wild to change the filter types from band-pass to notch or one of the fade filters and changing character.