Right now I’m cleaning up a typeface by comparing groups of instances with Ben Kiel’s Glyphproofer. I’m generating groups of instances, comparing them with Glyphproofer PDFs, then fixing problems by adding virtual masters. I think this could be streamlined into an all Glyphs workflow. This could be done by adding searchable tags to instances and an option to preview all active instances.
Adding tags would make it easy to activate and deactivate multiple instances in a large family without having to create project files. For example, all of the black instances are tagged black, all wide instances are tagged wide, and wide black gets tagged as both. A search box at the top of the instance list would display relevant instances just like the search box in the font panel.
Then add the ability to display active instances in the preview area of edit tabs. With this combination of tools a user could look at only relevant instances to see how they interpolate. Now a user can preview only certain instances to find problems that need to be addressed with virtual masters. No need to export fonts and use Glyphproofer or Indesign to compare instances!