Paul was Paul and Shelby has give a great view on why Paul was Paul.
Sure some of the apsotles had issues with him, wouldn't you have issues with one of the persecuters of your beliefs?
It took awhiel and they warmed up to him ,even if they didn't agree on HOW he preached the Gospel all the time.
Paul's preaching was based on what he heard from Christ as it was FILTERED through him, though he also didpreach the variosu creeds he learned from the apostles when he visited them 3 years after his conversion.
Paul didn't always "speak for Christ" a few times he spoke based on HIS views and there were times he made that clear and other times, not so much.
We do have to rememeber that Paul gave us one of the best and most Christ-like definitions of Love, we also have to remember that Paul's letters are letters to people that he KNEW and they KNEW HIM and as such, don't have to say everything about Christianity or Christ for that matter since we can safely assume that Paul had discussed these things in PERSON while preaching there.