Just as there is an outline-view, there should be a shape-view. I am incredibly tired of having to guess which parts of a path are part of a shape.

There should be a mode where the focus is the shapes that have been defined (e.g. through pathfinder or manually), and the status of any line in relation to a shape.

The overview should differentiate the status of every component by colour (e.g. part of a shape, part of multiple shapes, part of compound path etc) and then allow you to click on any element and see a list of which composites (regardless of if it's a group, compound path, shape or whatever) that it's part of.

This would make things a lot easier when trying to create shapes, remove unnecessary components, or see what isn't there to create a whole shape that you can fill etc.