When using nested components, currently the user needs to “edit” the parent component in order to access the specific instance of the child (that is logical enough).
However, we don’t generally want our clients editing components… and yet we do want to train them to update properties (that is why properties are so nice of course). In fact, we don’t really want to edit components ourselves more than we need to (human error, time, etc.).
I think I can speak for most people on these above sentiments. 
Therefore I propose that being able to “pass” child properties through/up to the parent’s property panel, grouped by the child components found in the parent, would be very beneficial.
This is rough, but for clarity it might resemble this:
