Do it.
Be sure to show how the mass tagger works in each one of them. Especially the pattern matching to extract data from filenames, I really like that feature.
./Artist/Year - Album/Track - Title.mp3
It'll work with any music player and you can organize it even on a toaster, as long as it has coreutils. I use plain old mplayer to listen to music, just cd into the directory I want and call a script I made which is basically a glorified `find | xargs mplayer` (actually outputs the filenames to a playlist and makes mplayer read from it in slave mode so I can control it with keyboard shortcuts - from other workspaces, etc).
For instance, add listening to tracks where an artist is featured to your system and you start having to account for it each time you bust out your coreutils. Move it into a tag and you only have to account for it when it is of interest.
I would expect that most operating systems can accept most characters. Right, path separators are out, there are binary characters that aren't allowed (but then again - you have a hard time printing those on your CD booklet), so I'm genuinely curious where this falls short.
I'm not sure whether there is the pattern matching feature (or a plugin), but I think it may be achieved using the Shellexec plugin and some scripting.
%genre% HAS progressive AND %added% DURING LAST 4 WEEKS
Not sure if it has all the other features you need, and it's a standalone tagger, but works very well.
