Just looking at the synoptic versions of the Gospel compared with John’s, you can see that we are probably missing a lot.
John had a much more personal point of view in his writings, as neither Mark nor Luke were direct witnesses (Matthew uses Mark as a source). John was a direct witness. He was the friend of Jesus who was the closest to Him of all the disciples (”the one Jesus loved”), so it is not surprising that he provided his own personal viewpoint.
I think that John understood the gestalt, the head-space if you will, of where Jesus was coming from, better than anybody. This is why I recommend to new seekers that they read John first.