Hi TT, please bear with me in some "speculation" :o)
It is easy to focus on "only" and minimize "begotten". Father "begets" son.
Our logic circles really prove nothing and don't get me wrong, I don't kno for sure either way, but IMO the Son does not "have" to be co-eternal with the Father because He is of the same essence. God can do and be whatever and whenever He wants.
However, there is no major denomination that will allow you to believe, even that the Son is co eternal but not co-equal ,and then allow you to be ordained, or in most cases, even fellowship. If you do not believe the Son is co-eternal, you are a devil from a cult, and you do not believe He is God so you are going to hell :o)
If you believe that God "begat" Jesus from within Himself in the beginning like a small sphere within a huge sphere for instance- you are a heretic or even a devil, but really, the concept does not violate anything in John chapter one. The Logos, as the smaller sphere would still be God and with God and In the beginning.
I am not sure what I believe(OMG!!!), or if I even believe it can be known with authority on this side of the veil- but I am highly suspect of ANY DOCTRINE that began among the bishops who became the Roman Catholic church, and over which people have been tortured and excommunicated from all the so-called "churches" that have come out of her.
What is seen through a glass darkly is just that, because "my ways are higher than your ways" and "if any man thinks he knows anything he knows not yet as he ought to know".
My whole point in these types of discussions is to point out the holes in the "logic" of dogmatists (I am not suggesting that you are one of those, I find you to be reasonable and open minded) always falls short in certain points. There are "possibilities" that cannot be reasonably eliminated and that should leave us all able to discuss them without fear of being cast as heretics or simpletons if we don't quite buy another persons view, or if we try to poke holes in some sects systematic theology :o)
The certification of some subjects as "above questioning" is one big reason we are in chaos/division/hostility in "churchianity" rather than in order, union and harmony in the New Jerusalem.
Jesus was "given" the name above every name because He pleased the Father
And, so it pleased the Father to "make all the fulness
dwell in Him".
In Him dwells the fulness of the deity in bodily form.
And the Word became flesh, and dwelt among us, and we saw His glory, glory as of the only begotten(monogenes) from the Father, full of grace and truth.
These verses and so many more can be viewed from differing perspectives by reasonable people of good intent within the house of fellowship.
For instance:
It
is possible that Jesus' Sonship is given, bestowed, as a result of obedience, not as a result of being in very nature God. Several verses indicate this (Phil 2:10,11;Acts 17:31) Jesus was tempted in all manner like as we are, because He found Himself born of a woman, born under law, born in sinful flesh. He overcame His flesh, which he inherited from his mother, (which she had from her father, Adam) by love for the Father- and thus overturned the sin matrix within the whole creation(yikes! :o).
That seed, planted, bearing fruit like unto itself, many sons unto glory! Born not of the will of the flesh or the will of man, but born of the will of God they will be revealed in glory and set the whole creation free from the sin matrix/death/chaos, etc. By that seed, the incorruptible seed implanted in our hearts, we are born again unto a "fervent love of the brethren". We have these great and precious promises that we may become partakers of the divine nature as the mustard seed becomes a tree in us. This is how we recognize one another as sons, and it is also how the world recognizes them(John 17, James 3:13-17, Acts 2 and 4, uh oh).
We are told God cannot be tempted with sin. I think it is trite to assert, "well the God in Jesus was not tempted, just the man". Listen, the God in me is not tempted either. Jesus was tempted "in all ways lie as we are". That indicates to me there are some things we may not fully understand about what Jesus was.
Peter declared(Act 2:32,33)
This Jesus
God has raised up, of which we are all witnesses.Therefore
being exalted to the right hand of God, and having received from the Father the promise of the Holy Spirit, He poured out this which you now see and hear.
The "right hand of God", being in the minds of biblical unitarians, the equivalent of Joseph at Pharoah's right hand "exercising all the power of Pharoah in his presence", by dispensation, is a workable theoretical view for me because Jesus Himself bears witness to the concept in many ways and the apostles define the relationship in that way in several places also.
Certainly this perspective can be drawn from 1 Cor 15:27,28 also
1Co 15:27 For "He has put all things under His feet."But when He says "all things are put under Him," it is evident that He who put all things under Him is excepted.
28 Now when all things are made subject to Him, then the Son Himself will also be subject to Him who put all things under Him, that God may be all in all.
These are all thoughts from my own musings- definitely not any attempt to advance a systematic theology or doctrine of the Godhead

The problem with systematic theologies is, Evrybody has one

. Very few people ever really search through the possiblities presented in their "opponents" system. Hence the dogmatism and division.