It’s really interesting how different we all experience the GUI. The muted, lighter, and more pastel color scheme with thin and not fully black outlines are much better for my brain. So there’s probably no outcome where one icon scheme will work for everyone, hence having user defined or dynamic/parametric icon schemes would be great (e.g. like Grasshopper 2). Which seems like it should be possible with the new SVG icons, maybe? One might add a menu to the appearance settings:
