I really like aeternal. It sounds like a few of her other songs in terms of arrangement and melody, but it has some personality that sets it apart. I guess you might call it a "well crafted" j-pop song overall and I don't think it's going to be the new "my all", but who knows. I'm not mad waiting two years for a song like this, she does them masterfully
Like the guitar solo i the way I am and again it's a nice song. Same goes for the rest, except I don't like W much.
We are the queens may not be a new song, but it's one of my favourite songs in "recent" times, so I'm glad it's getting a proper release. It's def. the standout track on this release.
I hope this albums breaks 20k.
As for the disappointing part, I think she's just being safe. Look at the difference in sales and I presume popularity between A one and colors... A one contains a much safer set of songs than colors, so does sixxx. I don't think it makes sense to expect anything wildly different from her these days. But I can understand that people are disappointed.