[sciurius]

Treating all section directives the same and using the label for repeat is an interesting idea. But what you call label is already intended as a margin label and may not be suitable for identification.

For example:
   

The next version of the ChordPro specification will introduce a more flexible syntax for directives, and this will allow the specification of proper identification labels.

I'd suggest to subscribe to the ChordPro user community https://groups.io/g/ChordPro/ . You ideas will be appreciated.