All he is doing is what Air Bison already do: fly around ;p Granted, that is pretty OP, but I dunno if if "flight bending" would count. Blood/plant/healing, lava/metal, and lightning/combustion are all pretty extreme extensions of the base "class". The key idea behind them all is you take the base element and tinker with shit that contains the base element, but aren't pure.
Maybe sound bending? You use your powers to mimic voices (by controlling the airflow to replicate a sound) or create massive sonic booms/sonic disruptions? That would be a pretty good hero class for air bending and have good applications in fighting.