Well, my in-laws bought me the +1 special edition for my birthday (yay for Japanese in-laws), and I'm actually listening to it right now. So far, it's not grabbing me like Scratch did. I think it's about as good as Circle so far (I'm like 2/3 through), and that album wasn't as good as Scratch. I don't really like the j-poppiness of it, which looking back is probably a side of her that did start on Scratch. The more j-poppy songs on Scratch, though, sounded more like diversions than really core songs. With this album, the j-pop is more front and center and the rock songs sound like the diversions. It sounds like more care and detail went into the pop songs than the rock songs, and there's more straight pop than on any of her other albums.
The DVD that comes with it is pretty good, though. I was expecting it to just have a few videos on it, like the Circle special edition (which I also have). I'm not sure what the Scratch SE had; I have the regular version of it (bought it used, didn't have a choice). But the +1 DVD's got three videos (Samantha, Yellow & Jasper), three live songs, and some sort of "experiment" program that I haven't watched yet because it's all in Japanese. The live songs were taken from a show that I'd heard about before; it was at a small club, which is really unusual for her these days. The songs themselves are all on the Live Scratch DVD as well, and they're probably better there, but it's cool to see her get back to her roots and play a stripped-down show again. It's kind of a counterpoint to the CD! They even included three separate "MC" segments at the end, all in a row, I guess just to show her interacting with the crowd. It's literally like 10 minutes of her just talking. I kinda wish they had just put a couple more songs on there instead, but it's overall more than I was expecting anyway.
I don't know the other bands you mention, which might explain my perspective.
If you mean Animo, who I mentioned, that's Kaela's old band. Here's a video with a couple of their songs, you can hear her roots:
http://www.youtube.com/watch?v=2sPlck6C_y4Here she is playing one of her Animo songs on her last tour; she hasn't forgotten:
http://www.youtube.com/watch?v=66l4f1nB8Cs