You're pretty much right with the intended usage - with a couple of minor notes.
- You can control-click on a node to quickly load more
- The genre and instruments can be changed whenever you like, but MuseNet will try to transition sensibly, so it might not be immediately obvious
Accidental deletion is a major problem right now, and is high on the to-fix list. Personally, I manage just using the save/load functionality, but it's not a great replacement.
I had hoped to get this more polished before sharing it, but other things came up and it got put to one side for now. Definitely open to pull requests if anyone wants to fix something, there's a long list of issues on the repo!
You're definitely right that it's not a very efficient use of the human. Another planned feature is the ability to directly edit or write the MIDI, allowing the user to say "I liked this option, but this one note was bad".
When writing MuseTree, I was imagining a user who enjoyed music, and wanted to try creating some music of their own, but couldn't just write something outright. With MuseTree, the only skill needed to write good music is the ability to recognize good music.