Related to Zettelksaten: if you want to follow the Folgezettel ID system, you may find helpful the ability to manage notes in the sidebar as a nested list without using Folders structure. This would allow you to expand or collapse sections and sub-sections in order to improve the way to view and work with the different branches. Similar to the way that Workflowy or Dynalist works
It is not about a list within the note but about managing notes as a nested list
Expanded Note list example
Collapsed Note list example