Feature requests for courses in garmin connect:
1) Duplicate courses.
Often I would like to use another course as the basis for a new one. This could be made easier by being able to duplicate an existing course and changing it's name. This is implemented in Strava courses.
2) Automatically generate suggested courses based on start, stop position and length.
A lot of the time I would like to do a 30 mile circular cycle route and it would be useful if courses in garmin connect could automatically generate suggestions. Additionally the suggested routes could be weighted towards those roads that are most commonly used by other users (like Strava heatmap). This type of thing has been implemented in plotaroute (https://www.plotaroute.com/routeplanner) and is handy.
3) Be able to create a new route based on an existing GPX file
I use other programs such as plotaroute and strava to create my routes. They both export GPX versions and it would be useful to import these into a new course in Garmin connect. At the moment you have to go through the clunky process of importing the GPX as an activity, converting it to a course and then deleting the activity.