Ayu never says after every album that its the best she's made. She says after every album that she loves the result, but not that its the BEST she's EVER made under her name. That statement is pretty powerful from her. I think she's made a really fulfilling album after a long time, and I can't wait to hear the whole thing in full.
And of course, she's going to love every album she puts out. its her music, and she wouldn't release it if she didn't like it.