The new features page on the site has been expanded a lot: grapheneos.org/features. Redundant content has been removed from the main page.
We'll likely make a section on past features to list out the many historical features that are no longer implemented as part of our changes.
Conversation
A section on past features could be divided into those that are now upstream/obsolete and ones that are not yet ported to the current OS (with links to each issue).
For now, the page only lists our current enhancements to AOSP 11 and doesn't go into much detail about most yet.