You should also be aware of the fact that for getting backed up by Google's "native" backup-to-cloud, an app must actively support that -- i.e. it must explicitely use the corresponding API, or it will not be included with those backups. While not all apps support this (<- euphemism), there's nothing excluded by Titanium Backup. As described, the latter backs up really everything -- while the former only backs up some data from some apps.
Another good thing to do from time to time is a full Nandroid backup, which is supported by most (all?) custom recovery images/modes (e.g. ClockWorkMod aka CWM). Once booted into Recovery, you can create a Nandroid backup (make sure to have enough free space on your sdcard), and having done this, you can move it from the card to your computer for safekeeping. If you've got enough space on your card, you could also keep the latest copy there: With Titanium backup, you can even extract single elements (such as a special app and its data) from a Nandroid backup. Or, if your system for some reason gets really messed up, you can restore it completely from this Nandroid backup -- again via the Custom Recovery.