A few adjustments?

“Do actions agree with words? There's your measure of reliability. Never confine yourself to the words.” 
― Frank Herbert, Chapterhouse: Dune

So, we're told, it's a fake - Christianity, that is.
"Like other great religions". writes historian John Roberts, "Christianity was not founded", but had to invent itself "in three or four centuries", increasingly loosing sight of the 'Jesus' of its early days, turning Him,  principally through Paul and the work of the early church, into a figure defined by the "awful and mysterious concept of Christ, the embodiment of the Godhead, the second person of the Trinity" (Triumph of the West, Chapter 2). This is the principal argument of all critical approaches to the New Testament - that we have essentially lost the real Jesus beneath all the religious inventions that came after He was no longer there to prevent this.

The form of Christianity, which the Gospels describe as unfolding in Galilee around AD 14-37, so clearly inscribed, for example, on the walls of Pompeii by AD 79 and spoken about by Tacitus following the fire in Rome in in AD 64, is to be understood as an elaborate deception - something which merely allowed men to make a name for themselves as they freely cherry-picked from the life of an obscure and essentially insignificant Jewish Rabbi to invent a new religion.

Is that what happened?

If we put aside the New Testament itself for a moment, it's pretty clear that Jesus wasn't someone that either the Jews or the authorities in Palestine at the time could ignore. History records that this man was a teacher during the time of Emperor Tiberius and when Pontius Pilate was governor of the district. It also confirms that He was executed, but in spite of this, His movement spread across the empire. Further non-christian materials also verify that this movement spoke of their founder, Christ, as God.
If we use these early records as pegging points, then we can very quickly establish some key information about the beginnings of Christianity -

It's key figure was a teacher in Judea.
He clearly became a threat to the authorities of the day.
These authorities executed Him because of the trouble He caused.
Those who followed Him believed Him to be 'Christ' - God with us.
His death did not end, but fueled the growth of the movement, which spread rapidly.
These events all happened at a particular time and place.

All of this can be gleaned from a few short entries in secular writings of the time, so given that is so, where is the "awful" process of inventing that critics say was required over the next 300 years? Was it  not the case, that these "awful" beliefs were in place when the Roman governor Tacitus expresses a similar disgust at Christianity's "deadly superstitions" in AD64!

What such records actually show is that the cardinal doctrines of Christianity, especially with regards to the person and life of Jesus, were there from the beginning of this faith, and that the further work of Paul and others in their writings and travels was to merely declare what was already established by the events that had occurred in Judea during the time of Pilate.

The real question to be faced with regards to Christianity is not the authenticity of its definition of the life and person of Jesus, but the ramifications of what the Gospels of the New Testament tells us about this person, and what that means for each of us.

Deification, for example, we are told, is something that is 'worked' into the religion later on, but is that so?

In the first chapter of the Gospel of Matthew, after tracing Jesus' family back to Abraham, the writer speaks of a miraculous conception which is a fulfillment of a promise recorded in the book of Isaiah regarding the coming of God Himself. In the next chapter, wise men come from a foreign land to worship the new born, who is protected from genocide. In the third chapter, as Jesus the grown man identifies with the repentant of His day, God speaks from heaven of His true identity.

It is this person who is at the core of Christianity from its earliest days, and who literally turns the ancient world upside down as those who knew and followed Him went out amidst great trail and cost to share the truth about who He was and what He had done. That is the same truth we must face in our day, and no manner of distraction can truly remove us from the imperative - that we need to take this person seriously, and give those events the deep consideration they so rightly deserve.