Seems to me that the best argument against Arianism is an openly NeoPlatonic one, such as this one offered by Victorinus:

In the flesh itself, therefore, life is present, that is, the Logos of life; it follows that life is present, wherefore the “Logos has been made flesh.” It is not astonishing then that the Logos has taken flesh mysteriously to come to the aid of the flesh and of man. But when he took flesh, he took the universal logos of flesh. Now for that reason he has triumphed, in the flesh, over the powers of all flesh, and for that reason he has come to the aid of all flesh, as was said in Isaiah: “All flesh will see you as the salvation of God,” and in the book of Psalms: “All flesh will come to you.” 

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Victorinus was influenced by NeoPlatonists, but his this paragraph “NeoPlatonic”? I’m not sure. It seems like the Incarnation as expressed in Paul’s epistles and GJohn.