This is kind of a 2-parter, offering a solution to an existing problem:
It would be very handy if the minutes/hours entered on a ticket, posted to the technician's calendar.

Personally, I like to visually see me and my technician's appointments on the Calendar, primarily because it helps to get a quick idea of how busy (billable) we are without building a report, and it also helps each of us remember exactly what job we were on and what day.

Before I realized adjusting existing calendar events caused the appointment to be cancelled and re-created (which also cancels the event in Outlook/Google Calendar if integrated), and also cancels and re-invites on the customer's end (causing confusion), I would go and adjust the appointment to match the time spent on a ticket.

Ex: Appointment created from a Ticket for 10am-11am, job lasts until 12:30p, after updating the ticket, go to the appointment and adjust the time from 10am-12:30pm.

If the ability to add time to the calendar were available, then we wouldn't have to worry about our customer's appointment invites cancelling and re-sending (maybe also have a toggle option to send/not-send an email when time is entered, but definitely Off by default)