Create a Drupal 8 version of the boilerplate.
Will this be different to the default structure when you do a composer based installation?
It would have to be, because with composer you have to manage the scaffold of files outside of the core directory.
I'd propose that boilerplate be for non-composer projects (core committed to git) and we direct people to https://github.com/drupal-composer/drupal-project if they want to use composer for all the things.
I believe based on https://12factor.net/ this needs to be moved to an auto build here is a started work. All you need is docker and docker compose then just execute:
https://github.com/acidaniel/docker-drupal
./up.sh
This will install as a profile your new site and don't need to track the contrib modules.