I am using external edition to VSC regularly on some of my notes and I would love to use it even more but there is some friction.
First this little quality of life improvement would help: [Feature Request] Save many superfluous clicks when using external editors
Then having this data loss bug fixed would also help: Joplin Desktop external edit feature sometimes causes data loss · Issue #15789 · laurent22/joplin · GitHub
But here I want to talk about opening many notes simultaneously in VSC which is very convenient for example in 2x2 panes etc. The issue is that I waste too much time and too many clicks reopening everything all over again from time to time.
All that could change if only the externally opened notes would persist after a Joplin Desktop app restart. Currently when you restart the app for some reason, all your previously externally edited notes are no longer so and you have to externally edit all of them again one by one.
The end goal would be to create a smooth and persistent experience of working simultaneously on many notes at once in an external editor. Restarting Joplin or rebooting your computer? No problem, everything is back like it was before and persistent. Or at least closer to that ideal than it currently is.