Toph's, erm, quent-essential
nature is a little off-putting — Seriously, "I'ma gonna fuck you up, bitchbender"? — and the semi-reveal that Azula was caught trying to kill her father
instead of leaving it vague make it a bit hard to swallow for me. Aang, Sokka and Azula are spot on though. Toph, like I said, is a bit too much like a Samuel L. Jackson-wannabe that's trying too hard, although sometimes she's in character. Katara is vaguely in character, although she doesn't seem to have too much of a role in later chapters.