The backups that TCH performs on a regular basis are to protect total loss if a system fails. It is by no means a substitute for customers backing up their own sites.
Having said that, the only backups required are when changes are made along with databases and email. I personally download all my mail daily to my own machine using POP access even though I do access my accounts using IMAP throughout the day. If I am away for an extended period of time, I download the email when I return.
Check out the Backup FAQ thread in the cPanel and Site Maintenance forum for using cron jobs to perform database backups as well as site backups to a remote server using FTP.
Remember, your data is your responsibility.