Really like the premise of this! But, as an individual contributor with hiring / leadership / planning responsibilities, I found that a lot of my highest priority work actually happens in the time between my calendar events.
The structure of this tool makes me think there should be a 1:1 mapping of hours worked to calendar events. Maybe it's a better fit for someone with the "manager's schedule" [1], or maybe you all do a better job of blocking out time for individual work on your calendars?
I see a lot of value in a tool like this though! The calendar rebalancing I frequently find myself doing is grouping like meetings (stacking interviews back to back) and maximizing the duration of meeting-free blocks of time (putting as many meetings on Monday as possible to free up later days in the week). If this could happen without me thinking about it I'd love it!