Always found this could be better to orient myself esp with complex geometry: Curves if e.g. extracted as boundary/face border would be overridden by the surface border/edges. So you can’t see any curves if they are overlapping. Hence I choose to give them 2 pixels width but then it gets very messy esp. if you have many curves as in my case with the extracted mesh wireframes (need to have them).
So it would be cool to set curves overlapping priority to always see them. Hope you understand.
In this screenshot I marked the actual curves (not visible)