For me the biggest issue is not being able to see the month at a glance and see the days with "X" amount of dots in them.
Now when I go to the month view I see a single dot. This doesn't tell me how many events I have for the day, let alone give me a sneak peak at what those events are.
I actually find myself hitting the search function from within the app so that I can see a list of all the items for that day.
The calendar app I think they messed up. If you look at the native app on google that allows you view the month and or day. This is how I do it in outlook and I wish I could do it in the native calendar app.
Granted I know we are limited by screen real estate but this still bugs me. If you look at the calendar app on the iPad this is how I like to see it.
Yep, a month full of dots. Make sure you fill this in