[DNSB]

My workflow uses two libraries. One library (mine is called Intake) gets newly added ebooks which need metadata, covers, editing plus whatever else I want to do to modify them, the second library with (mine is called Main) gets the ebooks after they have been massaged. Main is where I send to my ereaders, etc.

And yes, the library names are rather obvious and boring.

When I was first moving to using calibre, I used some bulk metadata downloads but there were always problems with a goodly percentage of the ebooks so I now use individual metadata downloads. This takes a bit longer than the bulk download but less time overall since I don't have to redo the bad metadata downloads.