There is only so much you can do with table design.
At some point you realise that table structure alone isn't enough.


Everything I've read in this thread points to you wanting a tree structure.
The structure you show in post #16 is a tree...
...and the best way of handling a tree is a treeview control.

Obviously a tv control isn't good for reporting... so you need to decide what kind of reporting you need...

Your output kinda has a relevance to the input.