With Drupal 8 maturing many organizations and teams are assembling and recreating distributions to use for people to start projects or use as full service applications.
Many of these require you to know how to setup and use composer and be comfortable setting up a site, databases, and some of the overall configuration of Drupal.
We've reviewed and put up some demo sites here and you can make your own assessments.
1. Open Social - A starter kit to social media has been rebuilt on Drupal 8 and has a great out the box feel to a social wall of posting information and group / events signups. Commenting and liking posts seems comfortable and development looks to have utilized contributed modules well for ongoing expansion into the updates to come in Drupal 8. Since we know some of you might struggle setting this up yourself, we have a instance up to temporarily play with here: http://opensocial.kwall.staging-preview.com/ Feel free to play around and create an account.
2. Open EDU - A higher ed starter kit built on lightning from Acquia and developed by our friends at ImageX have setup a Drupal 8 experience with content types for setting up some simple content that caters to a higher education need, like Open Social it's a great setup to build on top of and create your own theme and experience. Check out a demo site here: http://openedu.kwall.staging-preview.com/ to see how it lays out content and an architecture using Drupal fieldsets and panels to fit the responsive design.
If you are interested in what Drupal distributions are available in Drupal 8 there's a list here if you filter by Drupal 8 core https://www.drupal.org/project/project_distribution and even some really great options in Drupal 7 currently still active and very relevant.