One of the recommended practices for Scrum Masters/Team Coaches when facilitating Iteration Review is to begin to consider how and what to demo in Iteration Planning. This helps the team to have a clear vision of the expected outcome and to align their work with the iteration goals. It also facilitates the preparation and execution of the demo, as the team can anticipate the feedback and questions from the stakeholders. (Must be taken from SAFe 6 Scrum Master resources) Reference:
Iteration Review - Scaled Agile Framework
SAFe Scrum Master Course Outline

According to SAFe, one output of a successful Iteration Retrospective is the creation of a few improvement Stories that enter the Team Backlog for the next iteration. These stories reflect the team's agreement on what they can do better in terms of their process, practices, and performance. The improvement stories are visible and prioritized along with the other stories in the backlog. They help the team implement the concept of relentless improvement, which is one of the core values of SAFe.

Explanation/Reference:
https://www.scaledagileframework.com/metrics/