I haven't finished reading the whole article yet, but I want to comment on these things before I forget.
1. "the messages of Jesus and Paul were fundamentally different."
I don't believe they were.
Jesus said that he had come to give his life as a ransom for many, the Good Shepherd who lay down his life for the sheep; Paul preached Jesus crucified for us.
Jesus said that the greatest command was to love God and love your neighbour as yourself, Paul said that love was the fulfilment of the law.
Jesus and Paul had different audiences, and different emphases - obviously because one was preaching before Calvary and the resurrection, and the other one, afterwards. But I believe the central message of both was "believe in Jesus, who came to die for sinners so that they, and you, can be reconciled to God."
2. "Water baptism ceased during Paul's ministry".
Yet Paul said that he baptised Crispus, Gaius and Stephanus's family. In Acts 16, Lydia and her family were baptised, as were the jailer and his family, and the implication is that Paul baptised them.
(Edited because I posted before I had finished writing.)