Before you can talk about what the key features should be, you should identify what jobs the customer is hiring the product to do. That anchors the discussion;

Before you can talk about what the key features should be, you should identify what jobs the customer is hiring the product to do. That anchors the discussion; otherwise you'll be talking in a vacuum about whether to build feature X or Y without anchoring it to a job the product needs to do. The jobs to be done framework too brings the customer into the room. If we're building a photo editor, and I say, "I wouldn't use a feature that makes lips red and removes pimples", then we can talk about the job the photo editor is being hired to do, like "make me look pretty on Instagram". I can put forward my bias like "I don't care about that" and someone can counter that.