I'm currently looking for some backup tool, but each tool lacks some features. I'd like to
  • have rsync style (i.e. small) backups;
  • multiple backup-from locations per host;
  • backup should end on an webdav-device (but "local" in the filesystem will do for starters);
  • encrypts to gnupg (multiple keys), but restoring/looking at the diffs doesn't require to either gpg-agent-export the key to the restore location nor to transfer the content to the site where the gpg-key is;
  • allows to restore the version of previous days, and allows to view the differences created since then;
  • "feels like unix", i.e. configuration in some text-file etc etc.

I took a deeper look at duplicity, but the encryption to gnupg means I need to copy files around. Also the webdav-uploader has some issues if backups get too large (i.e. uploads take too long).

Any other hints? Or is it worth to start to enhance duplicity?

Update: I'd like to generate the backup on the backuped system, but to manage them (i.e. purge old versions) on the backup system. And of course restore to any host within my control. Without exposing any affected gpg key, but just the one-time key(s) for the affected backup(s).