As you jump on board and start using them, you probably, much like myself, just start using them without digging too deeply. And hence, you may not give a lot of thought to if you can make them more useful to you or not. At least for me in the beginning, I reluctantly started using some of them but really did not give it much thought beyond the basics.
For me, I've had an interesting affair with my Calendar, in that it's great to have and annotate events but I've found myself the victim of a few shortcomings. Shortcomings that were more my fault than anyone else.
CREATING CALENDAR EVENTS and Making Them Stand out
First off, I think making a calendar event is pretty straight forward.
(IF you're in Agenda Mode, click on the calendar view, pick the week, month or what have you,
-Click on the day you want to add an event,
-Type your event... like "Wife to Airport at 10am."
-Click 'Create Event.'
It knows you typed 10am and will put the event in the right slot.
In Depth, Unique Entries with Personality:
-Click on your day,
-Click 'Edit Event'
The 'Edit Event' screen has more options if you need more.
When you do a quickie entry, just typing the event and time, Google is smart enough to know where to put your event because you typed the time in the description.