Report for the most busiest and quietest class

 Currently, we don't have anything for future bookings but we do have the Staff Utilization report and also the Daily Schedule report for the past booking.
 

Steps on how to go to Staff Utilization Report: 

Steps on how to go to Daily Schedule Report:

 
You can also gather those classes with high booking count and minimal booking count by going to your Schedule tab and running through them manually.