Two ideas for a future version. As far as I know they aren't already implemented, but I'm discovering new features in MP3Tag by the minute so that might not actually mean something.
The ability to select a batch of files and then process them individually rather than as a whole. Right now, I have to select a file, search for the lyrics via web sources, select the next file, search for the lyrics, select the next, etc. So, it would be nice, if there was an optional mode to select a number of files and execute the script for one after the other.
An editor that allows you to move files up and down and sort them more freely. It would make playlist creation a lot easier.
All the best!