I think you're missing the point of Inbox. It's not supposed to replace Gmail, not now and not ever. It's an additional way of using Gmail, hence why its full name is actually "Inbox by Gmail".

Inbox is an attempt to make Gmail easier to use for the average user who has simple needs, so all the "power user" features you want aren't supposed to be in Inbox. If your needs are complicated, you can just use Gmail. Inbox doesn't really introduce any new features that Gmail cannot do, it simply reframes Gmail features in a different UI and workflow. For example, Inbox's "done" action is available in Gmail, but in Gmail it's called "archive". Same with Inbox's "bundles": they're just called "tabs" in Gmail.

As an Inbox user, I'm pretty happy with the state of Inbox. I don't need extra features get my stuff done in Inbox. Porting every Gmail feature to Inbox is missing the point.