Hello,
We use TimeZest for allowing a contact to select a maintenance window (which would be another good reason for: https://webview.canny.io//p/enable-recurring-scheduling).
One thing that would be nice is to specify custom calendars/scheduled for appointment types. I.e., we want these appointments scheduled only Fri/Sat between 8pm-11pm with overlapping enabled. So, we would create a custom calendar/schedule on this appointment type which would override our global schedule.