She seems rather balanced to me. To do much damage she has to build lots of attack damage items like Bloodthirster and Brutalizer. Even while building items like those she doesn't do very well against teams with a lot of tanky characters. My initial feelings are that she could use a slight buff in some way to counter tanky dps, but she is rather balanced against the rest of the champions.
She really is the first real burst damage AD caster since Pantheon's changes which turned him into a bit more sustained. With enough AD you can get Broken Wings doing 200 damage per slash, adding even more with her ultimate. The one thing I think is strange in the spotlight is Phreak always uses his ultimate just before using the wave ability, when it should be used at the start of a fight to buff all your abilities then use the wave to take out enemies or massively damage them before ducking out of the fight as you are probably close to dead.