With changing working practices we book desks at different locations during the week and/or are based at home. Our calendars then show everyone where we are. Even if we put those times down as "Free", the appointments take the appearance of a meeting taking up real estate in the calendar .
Instead of booking the appointment as "Free" it would be good to book the time as "Location Only" and this appointment then just shades the background of the calendar (as a separate layer to other appointments) rather than appearing as an appointment that gets in the way of real meetings.
This would be a MASSIVE improvement in the calendar.