I loved Kairi in Kh1 but we haven't got to see much of her since then, which leads me to favor Aqua more, I love her fighting style (mage based attacks are my chosen type) but her personality is irritating, the way she feels about light is the same way our villains would feel about darkness, that no balance can be struck (and Riku proves you can, fighting for good with the power of darkness). So magic wise Aqua, personality wise, Sora (until 3D where he's dumbed down to make Riku look smarter). Also Axel. Who can't love Axel/Lea.