Mainly the feature that has deletes first party cookies after a set time. This will make it so users automatically get rid of cookies on sites we probably won't ever visit again. Some customization for this enhancement to Enhanced Tracking Protection would be great as well and some thoughts I've thought of so far is setting a time for 1p cookies to expire, exceptions, and the option to reset expiration timer after visiting select sites again. That's all I've thought of so far, but I feel like it could be more robust.
I feel like this will greatly increase privacy and protection but also help clear the natural browsing bloat that we get over time.