First, the doctrine of the Trinity does not rise and fall on the plural pronouns references which by the way you have not even addressed-- you only deny the implication. In fact I normally do not go that route, for the exegesis of the texts such as Isa. 9:6; John 1:1, 8:24; 58; Col. 1:15-17; esp. 2:9; Titus 2:13; Heb. 1:8-10; and Rev. 5:13 clearly substantiate the Trinity. Now are you going to address these, or simply avoid them as usual?
Second, Justin Martyr, Athenagoras and other used them to show that God was multi-personal. They believed that God was multi-personal, not unitarian. If you would like I can paste to you the references, just as you have pasted most of your references.
Third, why would you point out that a great number of Trinitarian Christian scholars have long abandoned the notion that Genesis 1:26 implies a plurality of persons in the godhead. Rather, Christian scholars overwhelmingly agree that the plural pronoun in this verse is a reference to Gods ministering angels who were created previously, and the Almighty spoke majestically in the plural, consulting His heavenly court if in fact these Trinitarian scholars are wrong on the Trinity? A great number of scholars? That is a weak argument for why on earth would you believe anything a Trinitarian scholar would say? For I can provide a wealth of scholars (many more that you presented) that see the plural pronouns as multi-personal references of God, for recognized biblical theologians see God as triune whether or not they see the plural pronouns as Trinitarian.
Again the doctrine of the Trinity is based on the biblical teaching that 1. There is one God, 2. there are three persons that are and called theos (God) and 3, they are presented as personally distinct. You have not addressed that biblical data that I presented you only went to OT plural references as though Christians posit that the Trinity is based upon those references.
The point is this: if in Scripture Jesus is presented a fully God, then, your assumptions that God is unitarian and thus Jesus is not God is incorrect and the wrong God, and the since biblically Jesus is not the Father, nor is He a separate God, then, God revealed Himself in Scripture as triune.
I presented Titus 2:13 (and 2 Pet. 1:1) and John 1:1 to demonstrate that Jesus is exegetically presented as fully God. There are many other OT and NT passages that teach the full deity of Christ. But if you are not able to provide textual interaction of the particular texts in discussion I wish not to dialogue. Many folks only wish to present their views while ignoring what is presented to them in response, then, they merely cut and paste the work of others and/or ignore the exegetical interaction, seems to me you are doing just that. So if you respond, respond to the texts and refrain from merely postulating non related views that do not address the texts in discussion. Titus 2:3; John 1:1. The preexistence and deity of the Person of Jesus Christ is the very bedrock of historic biblical Christianity. So foundational is the deity and eternality of Jesus Christ:For if you should not believe that I AM, [egw eimi] Jesus exclaimed, You will perish in your sins (John 8:24; lit trans.).