I can say one thing about the Trinity: the Jehovah's Witnesses don't teach it right.
The mistake they make is that the Trinity is a dogma to teach people that God is Three. In reality, the dogma was designed to fight heresy by proving that God is only One.
Jews as you know don't believe in the Trinity. But when I left the Witnesses I was able to learn not only from my own personal research but from Judaism that Christianity is not teaching that God is Three, but that the Shema of Deuteronomy 6:4 (Sh'ma Yisra'eil Adonai Eloheinu Adonai echad) is not violated by its claims about Jesus.
The fact that Christians claim Jesus to be an incarnation of the God of Abraham in the flesh was taken up by the Gnostic Christians and Marcionism to teach that Jesus was a superior deity, more loving and powerful than the God of the Hebrews. The claim from Marcion of Sinope was that Jesus was an incarnation of a deity, and different god, but not the deity or the Messiah of the Hebrews.--Compare 1 John 2:22.
Eventually all the various heresies that sprung from Gnosticism and Marcionism got squelched when the Trinity doctrine was formalized. Instead of being a document that defines the Trinity in full detail, it is actually does the reverse. It is a formula of anathemas explaining what views of God are not valid.
As the Church recognized that Jesus was God in Epiphany, they also claimed that God was also the Spirit that was guiding the Church through Providence. But unlike the claims of the heretics, there was still only One, single God. The persons may be separate in identity, but not in substance. Christians were claiming they were only worshipping and having contact with the same, one God, whether it be the God of the Hebrews (the Father), the Son (Jesus, the Incarnation of God) or the Holy Spirit (the Providence of God).
The teaching of "one God in three Persons" is what the Trinity is about, not that God is three. The JW argument that claims Christendom is saying 1 + 1 + 1 = 3 is a misrepresentation. The teaching is that Jesus is the same God that appeared to the Patriarchs and so is the Holy Spirit.
Of significance, Jews don't reject the Trinity on the grounds argued by Jehovah's Witnesses. The problem is that Jews cannot accept the teaching that the Immortal One can become mortal and experience death. Jews have less of a problem recognizing God come in various forms (for instance, the Shekinah is God, the Angel of the Burning Bush was in a sense God, and the Theophany on Mt. Sinai was God, as was the manifestation of God that Moses and the elders of Israel ate before while on the mountain at Exodus 24:9-11). And yet, at the same time, all of these things is God and none of these things is God. The JW claim that confusion makes the Trinity invalid obviously doesn't read what the Jewish Scriptures have to say about God that closely.
Or you can validly take the view of nicolaou too (problem solved). But the whole, "THREE GODS" thing taught by the Witnesses is not correct. The Trinity Doctrine is designed to prevent that belief. Witnesses are just uneducated idiots who couldn't understand a creed even if they read it...Oh, wait. That is the case.