Having the ability to securely delete a call log would be very useful, many a time in the past users have created a call log and then realised it was for the wrong thing it was related to (be it a case or customer etc), the only way they can fix this is by deleting the detail and changing it to so “entered in error” which is a bit rubbish.
The simplest thing I would have thought to have is in user account security where the user can update time for all employees, why not add an option for can delete Call Logs for All Employees.