A pattern is first 1 Timothy 1:16 KJV! Paul was saved in Acts 9!
A pattern yes, the first person in the BOC, no.
Paul made it clear there were others in Christ before he was:
(Rom 16:7 KJV) Salute Andronicus and Junia, my kinsmen, and my fellowprisoners, who are of note among the apostles, who also were in Christ before me.
Paul was specially chosen by God to preach to the Gentiles:
(Acts 9:15 KJV) But the Lord said unto him, Go thy way: for he is a chosen vessel unto me, to bear my name before the Gentiles, and kings, and the children of Israel:
Notice the above says "to bear my name before the Gentiles"? It doesn't say "to preach a different gospel to the Gentiles"
Also, Christ Jesus said to Paul "I am Jesus whom thou persecutest". Paul (Saul) had been persecuting believers, that you claim were "kingdom" believers. Jesus Himself refers to the persecution of these believers as Himself, which once again proves these believers were part of the Body of Christ.
Your Dispensationalism is a mess.