You can edit Excel and Word documents on LibreOffice or OpenOffice. And Google calendar works pretty well with applications on Windows. Mac, Android and so on. Google allows you to export your data
And you can set up IMAP for email and sync that to multiple offline copies in case something terrible happens to Google.
I'd be more worried about FB to be honest. They've got nasty habit of blocking people for increasing amounts of time based on bogus complaints. But it depends what you do there. If you only use them for messaging and never actually post a status update, you'll be fine. Especially if you make sure you can contact people by another method if something happens to your account.