Starting with Blender 2.91 it is possible to give custom optimization settings to specific layers and objects.
This allows much more control over the generated ild file.
Also see ILD Render Layers

For example when you want to use particles, you could define that dots are not deleted for a specific object.

Note: these settings in Blender are only visible if “Freestyle Export Edges” or “Grease Pencil Export Strokes” is enabled

• the projector assignement can be changed and all options from the ILD Render Optimizations
• all optimization settings set here are valid for all objects within this layer (except they have their own settings)
• it is possible to load & save presets (exchange presets with ILD Render/Inkscape)

The option for layer specific settings are in Properties - View Layer Properties:

• changes all options from the ILD Render Optimizations for the selected object
• this is only visible when the selected object is a Mesh / Text / Grease Pencil / Metaball (because only these types ob objects are exported to ILD Render)
• Note: Gap Size and Reorder Paths options can only be set on a layer

Presets:

1. load all optimization settings from layer
2. load/save optimization settings (to exchange optimization settings with ILD Render/Inkscape)

The option for object specific settings are in Properties - Object Properties: