Team Calendar should be able to point out any conflicting events in the calendar.
Right now if a calendar has conflicting events, there is no indication about it and the user has to manually observe the time slots and identify conflicts.
This can be very handy, in situations where calendars are used for resource sharing, like meeting rooms reservations.
For example in the following snapshot, a calendar is being used by a team to share time slots for a meeting room.
But the calendar doesn't give any warning for the user booking the room and will cause confusion at 11am on Monday.
Team calendar should give indication that the event is conflicting. This indication can be anything like a small pop-up, warning the user when an overlapping event is created or as simple as something like following to highlight conflicting events.