“I have detected some animosity toward Paul by some Christians as if Paul preached another different gospel.”
Many want to dispense with Paul, because he was the “theologian” of the apostles. He was the most prolific writer, and explained the “mechanics” of salvation, sin, and redemption in the most detail. If you can throw out Paul, then the statements of the other writers may be vague enough for you to twist around into whatever kind of cult you want. As long as Paul remains, that is difficult.