This is going to sound lame but because phoenix currently only has 3 in-game moves in the final COP bcnm, i wouldn't mind phoenix just being like Odin and Alexander. Luminous Lance and Revelation is all we've seen it do and his 3rd move would make quite the grand astral flow perfect for the Odin and Alexander catagory.
Phoenix 3rd move is Redemption which Restores all HP and MP and increases TP to 300% for everybody within range.
To find phoenix we wouldn't have to really go to the Far-East, maybe go see Selh'teus in COP instead.