Yeah, I really do like this way of doing it. I might change the Vue example to do that. For React though, the HTML is usually empty, so it ends up hiding the dependencies within a tab that nobody looks at, so imports are a lot clearer.

Perhaps I could find a way to transform imports into script statements in the exported file. I'll have a think about it...

    Perhaps I could find a way to transform
    imports into script statements in the exported file

Uhh no! That would be even more hidden magic. The beauty of your platform really shines when there is no hidden process. When the user can transparently see what happens.

There really is no difference between Vue and React in this regard. The React demo without a server side toolchain looks like this:

https://frontarm.com/demoboard/?id=2e5ca405-b011-4d00-988d-2...

Packing up the imports into (a) boilerplate html and (b) boilerplate package.json would allow people to code stuff up quickly in your editor and then download it for integration in their own pipelines with minimal hassle (Maybe add buttons to download as zip with dependencies either in index.html or in packages.json?)