Hi Hartmut, I think your arguments hold, but it’s just one side of the story.
The other side of the story is that having our own installer, while being an additional burden, also means we can adapt it more easily and offer better integration—for instance, the fact that it knows about ‘operating-system’ declarations and services means that it could perform sanity checks, offer users to “browse” their OS declaration, and so on. And last but not least: the installer exists now, which makes the question kinda moot IMO. :-) Ludo’.