I also love how Heptabase allows you to create different canvas that you can spcially add and organize your notes onto. The main selling point if you can also draw different containers/area is that you can organically do things like a timeline or a kanban without needing a specialized plugin for every use case.
It’s nice also that is looks like an unlimited canvas, you can zoom out or in until you actually see the content of the notes and can also edit them in place, link them the way you want with a semantic of your choice to be displayed on the link.
Basically the plugin would just have to store for each note appearing in the view its x, y coordinates as well as the links between the notes to appear as arrow on that particular view and any additional grouping, color, background elements that should appear on the canvas (e.g. to create different areas to put notes in).