Lightbulb: instead of folders (except for reasons adjacent to processing), tags. Giving something two tags is pretty similar in a tag pane to nesting something 2 deep in a folder pane, and you get the option of having a thing in multiple tag groups, when you can’t have a thing in multiple folders.
The one loss, is I liked being able to create a new note and have it automatically in the same category (folder) as the previous note (because usually I create new notes of the same broad subject as the old). Is there a way I can do that with tags?