Mp3 Tagging Headache

I know most people simply label their Japanese mp3's as either "J-Pop" or "J-Rock", however in my case, my entire collection consists of 95% Japanese music. As a result, only using "J-Pop" and "J-Rock" on these files loses its point because it really doesn't work well in categorizing the music. How helpful is it to have half your music labeled as "J-Rock", and the other half "J-Pop"? Not very, obviously.

I need more specific genre labeling.

But further breaking down the genre is very very troublesome. Should I assign the genres based on the individual songs or individual artists? If I label genres by songs, I'll never be able to finish with my entire collection because there are just way too many files to relabel.

If I go with artists, what about the artists who suddenly change their style? Take Amuro Namie, for example, she used to be pop, but now with the latest 2 albums, she's all of a sudden R&B. Or m-flo, I'd call them R&B back when LISA was still with the group, but these days, they're very obviously hip-hop/rap. Or there are some artists who are just so eclectic that I'm at a complete loss.

The genres aside, there's also a problem with the artists' names. First of all, most times there are at least 2 versions to their names, Japanese and romanization. Angela Aki is also アンジェラ・アキ, SID is written as シド officially in Japanese media. I saw from somewhere that HYDE's name, when referred to in his solo work context, should be written all capitalized. When referred to in L'Arc~en~Ciel context, his name is "hyde", all lower-cased.

Then, some artists like to change their names in the same manner a foreign language student can't make up his mind about his new name in the language he studies. 雅 is aka miyabi is aka miyavi is aka 雅-miyavi- is aka MYV. Gazette aka ガゼット recently started writing their name as the GazettE. Kagrra, went from Crow to Kagrra to Kagrra, to KGR (in a few instances, probably miyavi influenced). Stop messing with us, please. Just pick a name and stick with it.

This is not all. Some artists love to confound us with weird symbols in their names. Take 関ジャニ∞, what the heck is this infinity sign? Oh, it's actually the number 8? What, are you serious? Why can't you just write "8" instead of rotating the symbol 90 degrees?

Mp3 tagging for Japanese music is one huge mess. I don't know what to do with it.