The clear ones on the pre-existence of the Son born as Jesus is stated by Jesus many times. How come you have not noted those? How come you do not recognize the Two Powers of Heaven that Jews realized in passages like Gen 15:1-5? You would have to be advocating that there are four persons in the Godhead if you want to deny this is one of the Godhead who became incarnate.
I feel some sadness for your state of blindness unless you are purposely blind to the scriptures.
You're going to have to do a lot better than using arguments that strongly imply "This is in the Bible because I say it is."
The reason your pre-existence argument is bad theology is because the same sort of things you say mean Jesus pre-existed apply to others. Human pre-existence is not a doctrine in Scripture, no matter how much it may seem like it's possible.
For example, one could argue people pre-existed based on Scripture, using your same line of bad reasoning:
Did Jeremiah pre-exist simply because God foreknew him?
Jeremiah 1
5Before I formed thee in the belly I knew thee; and before thou camest forth out of the womb I sanctified thee,
and I ordained thee a prophet unto the nations.
Did God intimately know David due to David pre-existing?
Psalm 139
13For thou hast possessed my reins: thou hast covered me in my mother's womb.
14I will praise thee; for I am fearfully
and wonderfully made: marvellous
are thy works; and
that my soul knoweth right well.
15My substance was not hid from thee, when I was made in secret, and curiously wrought in the lowest parts of the earth.
16Thine eyes did see my substance, yet being unperfect; and in thy book all
my members were written,
which in continuance were fashioned, when
as yet there was none of them.
How could God chose people who didn't pre-exist?
Ephesians 1
4According as
he hath chosen us in him before the foundation of the world, that we should be holy and without blame before him
in love: 5Having predestinated us unto the adoption of children by Jesus Christ to himself, according to the good pleasure of his will,
The common denominator is there are no examples of people pre-existing their birth, including Jesus.