I just need to give an extra shoutout to the layout hacks on The Accidentals. @Brad Struss​ pointed it out on a thread months ago and I made a note to read them more carefully. Those are some great ideas that really show the power of Lightning!

Not using the page layout anywhere on your Lightning Page is true out-of-the-box thinking! And user toggles with a Quick Action to show/hide more sections is very clever!