Currently Curriculum doesn't allow for any course controls like self-enrollment rules and approvals when a course is assigned to a curriculum. There are times when rules and approvals may be required for the courses within a curriculum (for example if a course has a fee or only a specific audience is allowed to enroll in the course). Would be great if individual course controls would carry over into a curriculum to give admins more control over the course enrollment capabilities of users that are assigned to the curriculum.
I agree, I would love the ability to have a learner earn a competency through a course completion or survey at the beginning of a curriculum to unlock additional courses later in that same curriculum would be a game changer. Also the ability to make groups available using the competency, prerequisites would be an awesome featuer and give the admins and course creators more control over the content.