I'm not sure if this is just an Android thing, but I can't change the notification tone for the Calendar. It's the same as my text message alert.

Is there something that can be done to add an option to change the notification tone?

Even better would be to have a different tone for each calendar, so I knew which calendar was pinging me. Because when they're all the same tone I just tune them out. Stuff that's critically important could have a very distinctive tone, that way I make sure I always check them straight away.