Permission boundaries in AWS IAM service (official docs) is one of the most important mechanisms which helps developers and security specialists to set a permission safety net. From my experience, it is an especially important feature to use when working with multiple AWS accounts in an organization.
The newest player on the TACO market is positioning itself as an alternative to Atlantis. It offers GitHub integration for Terraform pull-requests, centralized audit log, customer support. They are currently in a very early stage.