I know what you mean, orangedream. When I first got into ayu in 2000, I found it fascinating that her lyrics were 100% japanese when other artists seemed to love random english so much. She said in an interview at the time that she was only comfortable expressing herself in Japanese. I remember being shocked at the english word "Yes" appearing in "AUDIENCE"! It was just like "waaaaaaah!?"
Then when she took her trip to HK in 2002 and saw how many fans she had there, she suddenly started sticking English in her songs. I mean it was welcome at the time, but later, in retrospect, I'd realize that that was when the quality of Ayu's music really started to decline.
Now that she was writing with listeners outside of Japan in mind, she started getting more & more "safe" with her music and less & less personal.
But she did start easing up on the English. For a long time it felt like she hardly had ANY songs that were 100% Japanese, but i feel like those songs do come up more often now. I do wish she'd back off the English almost completely, because I do feel like she WANTS to be personal but feels like she can't be because of the listeners. That said, the English she DOES use now is the English she's comfortable with (which is why it's so simplistic sounding) so I'm fine with what little she uses now. It bugged me for ages cuz it didn't feel like her talking, but now it does so it's fine with me.
My main concern is that her message gets across in her lyrics. Now that it seems to be doing that, the English doesn't bother me as much as it used to.