^ In 1998 hitomi stopped working with TK for more creative control and became bigger than she already was. So assuming Ayu started with him in like 1995 and did the same thing her legacy could have potentially been bigger
I can't imagine what he would give her, probably typical cute-ish j-pop songs like he did for yuchida yuki and mizuki alisa? dumbed down versions of tomomi kahala songs, 4th member of dos...the possibilities are endless~