Hello everyone,
For me it would make sense to create a table of contents (TOC) feature where you would add certain elements to a table of contents. It would be best to allow to maintain a hierachy of the document indentation levels are shown in the TOC. Instead of a bookmark that is flat it creates a deeper sense of quickly linking to elements within a document.
H1 H2 H3 would be automatically added to the TOC and you could indicate other nodes to be added to the TOC
This could be added to the bottom of the Bookmarks Pane or in the document view or any other place that is deemed meaningful. This means the Bookmarks list becomes hierarchical as well.