I still wouldn't call this behavior a bug. This is the exact behavior that plenty of people need, so a whole sale change to course specific context would be a regression for us.
I see you added this request to the tracker, but I disagree with your characterization. Instead, a new feature request to add the ability to choose the context would more appropriate.
I'd also say that the other two complaints are best served by feature requests as neither are technically a bug. A bug is when something doesn't function the way it was intended, in this case each function behaves exactly the way it was designed and are perfectly usable for many scenarios.
However, I would agree that adding a way to set the global default for whether an event appears on the calendar or not and an easy way to remove events from the calendar would be useful new features.