Pinterest Embed Support is a good idea. However, are there are any chances of bringing back Instagram Embed. I know this was Facebook's decision to discontinue this, however, not sure if WordPress has reached out to them to work this out. I am pretty sure it's a feature that is heavily requested.

Also, a block that should be included in Gutenberg is the Table of Content (in my opinion). Most of us have other plugins or add-ons. This is a feature that most bloggers/WordPress users will benefit from.