Re:drawing schematics

I think my record for a pcb is 32 pages. All flat, no heirarchies.

That would have been hard to make sense of. Hierarchical design is a useful way of breaking up a circuit into a manageable number of minimally connected blocks.

Once you have worked out what each of the blocks is contributing to the other blocks and to the output of the circuit as whole you can have a pretty complete idea of what is going on.

Documentation needs to be intelligible if it is going to be of any use.

The bill of materials may be all that the buyers need, but even they need to know which parts are crucial.

Service engineers need to know quite a lot more.