In the time picker allow customization of time intervals on the minutes wheel. So instead of having all 60 minutes I could have 5 min. intervals, 10 min. intervals, 15 minute intervals, or 30 min. intervals. Since I round everything to the nearest half hour when this would make putting in past jobs a lot quicker.
This was a request some time back. I understand why you would not want to change the intervals, how about if you put 00, 15, 30, and 45 buttons that make the selector jump to that time selection.
