well I will tell you what I found to be easiest when I was imported adding what seemed like a zillion books.
Added all of the books and there were a lot. Took me two days to do this in chunks of 1000.
Lots were dups of course.
Then I did bulk metadata fetches and the metadata fetching was a lot less adequate, the series metadata was not downloaded at that time and a lot of it was butt ugly. The metadata itself is much better at the place it is fetched from these days
Then I sorted by title and went down the list and used the bulk edit screen to swap author title where it was easy to spot.
Then I sorted by author and did the same thing.
Then in batches I bulk downloaded the metadata with the option set not to change the title or author.
Then I checked for duplicates, author sort etc.
Took me quite a while. As I was reaching the end along came the
quality check and the duplicate check plugins. I would have killed to have these earlier, but they still were useful.
Prior to biting the bullet and taking the just get it done approach I had spent weeks and weeks trying different methods of inputting books and data, saving to disk with different filenames, and generally getting nowhere.
I hope you are at least getting mostly good results. Me I would be happy one day and a week later wonder what was I thinking.
Now my books are titled and seriesed in a pretty consistent manner, but they still aren't perfect. Darn close though
Helen