I agree: A Panes view is the most powerful way of working with this kind of data.
After you have your list in your Panes, you'll probably notice patterns. Simple stuff like [Composer] is empty. Or [Composer] contains certain characters. Or more advanced things like, [Artist] contains parenthesis or square brackets.
You can then write a Panes "saved search" for these patterns. These are called Search Lists; they are a Panes type. When you edit a Pane, you can make it a Search List type, and then build a list of searches. These searches can use all of the expression language, including Regular Expressions, or anything else you want.
This way, you can narrow your results, simply by clicking on the appropriate saved search.
The next technique is to make a custom field with a name something like [Composer Approved]. Make this a checkbox field, and simply check it for all of the files that have the correct [Composer] tag. *Then* you make another Search list Pane which hides all files that have [Composer Approved] set to 1 (checked) !
So, as you go along, you end up with less and less files that show up in your Panes view because you are fixing them, and then marking them as "approved".
I've used this technique to build numerous views for doing maintenance. It works pretty well.
Good luck.
Brian.