Thanks for the suggestion. The biggest issue I see with this feature is that this will make the UI a lot more complicated. I am not sure how this could be included in a way that does not make the current features/UI a lot more complicated and also on the other hand allow users to easily see which avoidances are used per leg/segment.
Even with the current visualisation quite a lot of people struggle to understand the avoidances and wonder why Kurviger is not using for example the motorway, yet they enabled motorway avoidance. So making this even more complicated feels wrong.
I am open to discussing this, but we would need a good solution for this and I am a bit pessimistic we can find something without overcomplicating the UI.
For now I would recommend to split your route into multiple parts and set the motorway avoidance for these routes individually.