The doctrine of the Trinity was developed over about 300 years by the Church.
I agree with much of what you state, although the Doctrine of the Trinity is fairly commonly accepted. So much so accepted, that rejection of the Trinity casts one in the category of cult.
Instead of arguing the point, I would recommend studying the Scriptures, and make an accounting for every reference to God, and how each person of the Godhead is addressed. Let God reveal Himself to you by His Provision.
He already has.
He already has.