Well, to be fair, the others weren't going around giving people the impression that they considered themselves the King of the Jews. Both the Jewish authorities and the Procurator had to be a bit concerned about that - whether it was true or misinterpretation is, at this point, probably verifiable only if somebody invents a time machine and goes back to take a look.
Yes, crucifixion was a horrible death. I learned a lot more about it than I ever wanted to, in the course of doing a favor for somebody on the RPG forum I used to belong to. He was writing a Highlander story about a Roman soldier, and asked me for recommendations of historically correct methods of execution used during the late Republic era that would trigger the process by which a pre-Immortal becomes an Immortal. The only two provisos were that the execution method had to be fast and for obvious reasons, it couldn't involve beheading.
As somebody who enjoys good fanfic, I liked the story - even when it got to the chapter when the soldier eventually meets Jesus post-execution and discovers that Jesus was an Immortal (crucifixion by itself can be a slow process, but the spear business... that's what triggered it).
As somebody who's into real-world Roman history, I can only take this seriously if you A. Can provide convincing proof that Jesus actually existed; and B. Jesus was somebody with a nice idea that people should be kind and considerate toward each other and who had a charismatic personality, but who also had no supernatural abilities or traits whatsoever.
Since they argued whether Jesus was God or human for over 300 years after, which part was made up? They knew he claimed to be God; that is what they wrote. Some thought he was never human. When you start to vote on how the majority believes it goes downhill from there.
And it was not that God could not take on human form. The Hebrews wrote about many instances where God appeared in human form. This time though, it was God in the womb of a human female, whose body developed as a normal human, and not just a human shell. That Jesus claimed God as his father was just a human conceptualization of a normal human condition. The birth of Jesus was the only way God would experience humanity from baby to adult.
As for experiencing pain and even death, was the point. Whether or not the beatings during the trial were any worse than normal may be speculation. The point about the death was that he died of his own free will. He was dead before the soldiers had to pierce his side to make sure he was dead.
When writing down accounts, and the point anything could have been refuted, but was left to stand, Jesus was pronounced dead, and then the Roman soldiers made sure of that fact. His body was handed over to the Jews. The demand for death was met. The Jews took full responsibility for the act, and relieved the Romans of any further legal actions. The Jews could not have legally done what they wanted to do.
They wanted Jesus to be dealt with and brought up false charges. Pilate found nothing wrong either, but to qwell any riots, and no skin off his back, went ahead and granted the Jews their wishes.
Obviously Jesus, did not want any riots and his resurrection was kept out of the public scrutiny for 40 days. At least to the point it would not start any riots nor stir up any more trouble between the Jews and Romans. I suppose some would say Jesus was just a bump on the rocky road between the Jews and Romans, but the temple was destroyed soon after. There were hundreds of writings to collaborate the reality of the account. It does not sound like the Romans or Jews were able to refute it, neither did it dissappear from the historic record. For all general purposes, it happened and was forgotten by all the authority involved in the manner. That did not stop his followers from taking the facts all over the known Roman controlled world.