So it can be quite helpful to take a look at the available times that your event participants have before scheduling anything. You can do this by selecting a time in the calendar, editing the event details and then clicking on the "Find a Time" link in the middle of the event editing page. Just don't forget to add your participants before going to "Find a Time" or else the only schedule that you will se will be your own.
There is a way on the user end to specify when their working hours are that will pop up a notification on the event scheduler's end. You can modify this setting from within your Google Calendar settings by clicking on the upper right hand gear in one of your calendar windows.
Sometimes scheduling things with larger groups of people can be difficult but hopefully utilizing these two options from within your calendar can help you to better manage time for both you and others. Do you know of any other ways that you like to using the scheduling features within Google Calendar?