Instead of Notebook and SubNotebook, I like using one note as a content page and insert other notes link into this one. As below:
And often I found two notes that are very related and I put their MarkdownLink as hyperlinks inside each other.
I found Notion's subpage is very like the way I would like to organize my notes. Instead of Notebook and subNotebook, I like to use command + g to fuzzy find the note I want and jump to related notes embedded inside this note I just found.
Feature
So it will be very nice if I can just insert a NoteLink into the current curet's position and create the new note here. Better, I can jump to the note like go to definition function in IDEA and continue to add notes inside it.