I have no idea if this is difficult to program, or even useful for a lot of people, but here's a feature idea:
Exports can be heavily customized with complex templates, but the "tag from file" feature is limited to a single line formatting, the file format itself being restricted to "1 track = 1 line". It would be nice to be able to use a saved template instead of the single line formatting. Then we could import tags from any txt/html/xml file.
The best way would be to be able to use the exact same template used for export, of course. Hope I'm clear.