Yes, backup and restore is far and away the biggest thing people want out of TWRP over and above the "standard" recovery.
The main thing I'm working on now is an archiver. It will be able to backup and restore directly from Android, no recovery required. Among other things, it will feature compression, encryption, incremental backups, and both local / remote storage. And it will work on any Linux system, not just Android. I plan to use on my own systems once it's working well.