Paul’s capable written Greek and his Roman citizen status raise a lot of questions about his life. He must have come from a wealthy, elite Jewish family.
We know the Seleucids turned Palestine into a society dominated by a Greek-speaking elite and that the Jewish Hasmonean kings who wrested independence from them were Greek speakers too, probably native speakers.
They were often criticized for not being Jewish enough. In any case, outside the ruling elite and perhaps an upper crust of top merchants, Greek was very uncommon in Palestine.
As the Romans gradually dominated Palestine, they did what they always did. They awarded Roman citizenship to leading and ruling families in return for loyalty. Citizenship was a rare gift, hereditary, and not handed out for trivialities.
Paul’s family must have been pretty special to both speak good Greek and have Roman citizenship.
He probably had his own money, which could help explain his travels around the Mediterranean, incredibly expensive endeavors.
Whatever it is that he made, tents or otherwise, he very likely did not do it with his own hands.
All of this to say that his illegal persecution of Christians is psychologically interesting. Here we have a man well connected with the cultural, Greek-speaking elite of the region and equally well connected with the powerful Romans who were just coming into dominance.
Yet somehow, he was willing to commit criminal acts against proto-Christians. This is strange. Well, it’s more than strange. We have evidence that the earliest Christians had very little conflict with Jews in general. We know of at least two 3rd century synagogues, one in Alexandria the other in Damascus, in which communities of Jews and Christians seemed to share facilities.
Paul’s story is mysterious and little known. What motivated him is never addressed in his own writings.
As you point out, a lot of our common assumptions are incorrect. What we learn in church has little relationship to who Paul must really have been.
Given he is one of the early founders of Christianity, we should probably strive to know much more about him.