Hello @davidblood,
I hope you’re doing well.
Actually, you can set your BetterDocs archive to the root page by following these –
First, you need to create a custom page using BetterDocs shortcodes. You will get BetterDocs shortcodes from BetterDocs > Settings > Shortcodes. Please check this screencast – https://d.pr/v/gdHQEr
Now you need to uncheck the Enable Built-In documentation page and then you will be able to select your custom page from the BetterDocs Setting. Please check this screenshot here – https://d.pr/i/we4hJc
After doing these now you can select that page as your homepage from WP Admin Dashboard > Settings > Reading > Your homepage displays (here select the page that you created) and click on Save Changes.
Actually, This is the way how you can make the BetterDocs archive your root page since native WordPress Custom Post Type works like this. I hope it will help you out. Also, you can check our docs here to learn more about BetterDocs – https://betterdocs.co/docs/
Thank you.