Summarizing my thoughts
I'm in the middle of a gigantic cross-disciplinary reading project now with the purpose of articulating in detail the connection between Catholic phenomenology and the authentic and ancient Trinitarian theology of the Christian West, as contrasted with both the inauthentic innovation of Protestantism and the oversimplified view of neo-Thomism. It's a far bigger subject than I can possibly claim to analyze in detail, but I have become convinced that it is necessary to do what I can to defend the claims of the Catholic Church against the assaults of neo-patristic scholarship. That's not to denigrate the work of Meyendorff, Lossky, or Romanides in its entirety, but they simply aren't sensitive to the antecedents of Western theology, nor the differences between that theology and the Origenism of which the West is accused. Catholic scholarship bears a significant portion of the blame for that difficulty, having been inclined toward explaining the past in terms of a "nature-grace dichotomy" with the result that either the true opinion of many theologians was suppressed or their wisdom was neglected as "Neoplatonism" or some other equally dismissive classification. But the Eastern response, both in the past and the present, has been so severe as to cut off the branch on which they were sitting.
My thesis, as it stands now, is that there have been two principal and complementary views of the Trinity. In itself, that is nothing other than what Catholics have been saying for centuries. But where Catholic scholars have failed is in identifying the ancient sources of these doctrines, thus leaving themselves open to the charge of innovation or of unknowing adoption of discredited Greek themes. This contributes to the erroneous notion that the East has somehow consciously worked through difficulties of which the West is unaware. Unfortunately, that notion could not be farther from the truth.
The views of the Trinity of which I speak were the direct result of the struggle against later Arianism using Neoplatonic philosophical concepts in the fourth century. In the West, these antecedents most clearly come through Neoplatonists Caius Marius Victorinus, St. Hilary of Poitiers, St. Ambrose, and St. Augustine; in the East, they are mediated by St. Athanasius and the Cappadocian Fathers. The culmination of these theories was the harmonious meeting between the teachings of St. Leo the Great and St. Cyril of Alexandria in the Council of Chalcedon. For polemical reasons, it has become fashionable to cast Chalcedon as a victory for one side or the other, as St. Leo is judged against the standard of St. Cyril or vice versa. What this analysis (sadly) misses is the common origin of both teachings and the reason they could be so easily harmonized. Far from being a case of "bad" Neoplatonism which leads to Origenism on the one hand and "good" Neoplatonism on the other, both East and West incorporated the SAME fundamental insight about the goodness of creation and the true divinity of the Son to reject Arianism.
The basic framework of the two views was the Scriptural teaching that God was the Power and Wisdom of God (1 Cor. 1:24). As Michel Barnes documents in The Power of God: Dunamis in Gregory of Nyssa's Trinitarian Theology, there were at least two separate Christian veins of thought about this passage, one of which emphasized that unity of power ("dunamis") implied unity of nature (the Cappadocian school) and another which followed Porphyry's study of the Chaldean Oracles in conceiving the complementarity of multiple powers as an expression of unity (specifically, Form/One, Power, and Intellect). This latter school, which Barnes describes as "primitive," was first suggested by St. Athanasius's emphasis on the title "Power of God." A difficulty arose when the "two-powers" formulation was used to argue that the Son was a distinct Power from the Father, so that the Son was given the power to create as a kind of Demiurge, allowing the Father to remain remote from creation. The Nyssen's answer to the Eunomians was based on the identification of "power" with the distinctive ability of an ousia, so that the identity of the Son's Power with the Fathers illustrates a unity of ousia. An analogous argument is made to the "activity" (energeia) of the Holy Spirit, so that He too is of one substance with the Father. The important part of this is that it affirms the goodness and will of the Father for creation contra any theory of Demiurge, an Origenist concept of pre-existing souls that fall into creation, or a Plotinian theory of undescended souls; the creative power is the same for the entire Trinity.
In the West, the analysis took a different tack. It meaningfully began with Tertullian's response to patripassianism, seen in Chapter 7 of Against Praxeas, where Tertullian addresses the use of "form of God" in Phil. 2:5-7 as being a substantive mode of existence, a Person. This sets out the Western model of Person, which is a forerunner of Nicaea, in that it distinguishes personhood by the begetting of the Son from the Father while identifying them in substance. I would argue that it also suggests the identification of personhood in the West with a kind of expression. And that, I would argue, is exactly where the distinction between the two traditions took place. The primary question in Western thought became manifestation, expression, which meant that the roles of the Son and the Holy Spirit became primary in apologetics against heresies. Hence, the "primitive" view fell more naturally into the West's emphasis on the form (existence), as Christ was the unique manifestation of the Power of God just as the Holy Spirit was the unique manifestation of the Gift (or Love) of God. This also provided a bridge between the economic and the immanent in Western thought, in that the form of God was an immanent concept that was fittingly tied to the economic concept. The connection is made explicit in Book IX and Book XI of St. Hilary's On the Trinity, in which St. Hilary ties our own salvation to being conformed to the form of God, which no one had seen except in faith before the Transfiguration and which will only be experienced as a true beatific vision when we are glorified in Heaven. It also played a significant role in the Western fight against Homoianism. That this emphasis on manifestation led rather naturally to the use of the filioque becomes evident in St. Leo the Great's Quam laudabiliter, in which he gives the following clear indication that he considers the Spirit to proceed from both the Father and the Son in terms of personal existence:
And so under the first head is shown what unholy views they hold about the Divine Trinity: they affirm that the person of the Father, the Son, and the Holy Ghost is one and the same, as if the same GOD were named now Father, now Son, and now Holy Ghost: and as if He who begot were not one, He who was begotten, another, and He who proceeded from both, yet another; but an undivided unity must be understood, spoken of under three names, indeed, but not consisting of three persons.
Now, according to the polemical view, the West would simply be a collection of backwards theological hicks who, never having confronted Origenism directly, simply fumbled their way through an often-inconsistent orthodoxy that was eventually lost during the Carolingian era because of the Western inability to distinguish theology and economy. I think that is simply nonsense. The reason wasn't that the West viewed "divinity as causality" (like the Origenist view of the essence being prior to the Father) or believe in "absolute divine simplicity" or any other such thing. Rather, the Father, as autotheos, has the hypostasis and form (energies) of God all at once, so that neither the hypostatic generation/procession and manifestation can be said to be logically prior to the other. If there is no interval between the Father having existence and existing, then neither is there any interval between the Father causing the persons and giving them of His substance. And contrary to the Eastern Fathers having rejected this understanding, it appears to me that they were more concerned with energeia as applied to creation than manifestation in the immanent Trinity, not going into inordinate detail regarding perichoresis or the relation between immanent and economic perichoresis, particularly since the singular nature of the divine power was specifically tied to creatio ex nihilo. The Eastern Fathers were concerned about dualism for certain, so that suggesting that the Trinity was generated by "relations of opposition" in the sense of there needing to be different kind of being would have been absolutely rejected, but that in itself has nothing to do with the Western theology of form.
Moreover, the agreement between St. Leo and St. Cyril strikes me as quite decisive. In the monograph The Appropriation of Divine Life in Cyril of Alexandria, Daniel A. Keating notes that the Christological agreement on the significance of the Incarnation of St. Cyril, St. Leo, and St. Augustine is quite remarkable in itself, but on the flip side, the significance given to the moral/ethical relationship with the Holy Spirit is also far more than the allegation of St. Cyril's supposedly "metaphysical" account of salvation would allow. To me, it seems relatively clear that Palamism (and its predecessors at Blachernae) and the conflicts of the Carolingian era are being read back into the fourth century at the expense of truth (and indeed, a hypertraditionalist account of the theology/economy distinction has actually caused denial of true dogma among some Orthodox Christians). On the contrary, it seems to me that the "form of God/form of a servant" account has been the consistent doctrinal teaching in the West from the fourth century and that this teaching was entirely harmonious with the Cappadocian account. Unfortunately, later critics (not to mention some later Western interpreters) have simply looked at it through alien philosophical lenses to infer causes, conclusions, and contradictions that simply aren't there. But the West has always looked at form and manifestation in reality, intrinsically focused on the Self/Other dichotomy studied in phenomenology, as the fundamental principle of theology/economy and transcendence, not to mention language, politics, and a host of other areas.