> I really miss Google Inbox

I very much agree. Also really miss the ability to quickly group related emails.

(And no, that was not the same as adding a label; for one, the whole group simply appeared as one "bigger" email in the Inbox. It was a bit like a thread that you can manually add emails to.)

When everybody got kicked out of Inbox I happened to have a group of about ten emails related to an upcoming trip. Those ten emails got de-grouped and scattered all around in the ordinary gmail interface. I would have appreciated a smoother transition...