Many of Inbox's features were moved over, such as Snoozing emails, but far from all of the features. I doubt they will move over more — if they had wanted to they would have done it when they shut down Inbox.

The biggest feature I miss from Inbox is the integration of TODOs and emails: you could create editable TODOs in your inbox as easily as composing a new email, and when viewing am email thread, you could create a TODO attached to an email thread (e.g. “review the attached document and reply with my feedback”).