Kuu has been the Queen of Live since 2008 for me. Her lives never fail to blow me away because they're so different every time, her vocals are just plain gorgeous and she has a theme in every concert. This girl is awesome
(and I don't understand in what way they're similar to Ayu's. I find Kuu's concerts completely different in every way lol) with her cool stunts she does (like what she did with POP DIVA on Dejavu Tour and Can We Go Back on UNIVERSE TOUR). Kuu is the Queen.
But I'm not saying Namie is bad either. I really adore her complicated dance moves; when I watched Live Style 2006 for the first time I had no idea what to wait but I was totally mind blown. It was so awesome.
I haven't watched Live Style 2011 yet (haven't had any time) but she definitely isn't a bad performer either though she doesn't always keep my interest up for too long, but I don't care because her dancing looks awesome. ^.^
I don't know about BoA because I have only seen few TV performances and not any full concerts but she dances quite well, too.