You always conveniently forget to mention that Paul was the Apostle to the Gentiles who called out Judaizer Supremicists from imposing their Legalisms.The Church is Israel. The Bride is Israel.
The Church (ekklesia = "called out [ones]") was founded originally in the desert at the time of the Tabernacle. The children of Israel were "called out" of Egypt the same as baby Jesus was "called out" of Egypt, only the term in the OT is "Great Congregation." And this Great Congregation were the twelve tribes of the children of Israel.
8 Also at the same time Solomon kept the feast seven days, and all Israel with him, a very great congregation, from the entering in of Hamath unto the river of Egypt. 2 Chron. 7:8.
13 And there assembled at Jerusalem much people to keep the feast of unleavened bread in the second month, a very great congregation. 2 Chron. 30:13.
18 I will give thee thanks in the great congregation: I will praise thee among much people. Psalm 35:18.
Nowhere in the Hebrew Scripture are Gentiles called "Olive tree" let alone "wild" Olive tree.
Cornelius was a God-Fearer. The "devout" is a reference to being a God-Fearer however they/he was not circumcised. They committed everything to God and His Torah except circumcision for one reason or the other. Still, they and proselytes were closest to the commonwealth of Israel (citizenship) and were allied with the people of Israel in all ways except circumcision and were the first Gentiles to hear about Jesus of Nazareth and the testimony of His life and the Presence in Israel of their Holy Spirit of Promise and while in the synagogues every sabbath heard the message from other Jewish Christians that their Messiah had come and the gospel (good news) about it was that God has kept His Promise (Deut. 18:15, 18.)
Christ promised to build His Church, and this began with the Advent of the Holy Spirit on the day of the Feast of Harvest (Pentecost) and the Church Christ built was populated by Jews. For four decades until the destruction of the Second Jewish Temple Christ was building His Church and with the destruction of the Temple halted the building this Carpenter began until the Times of the Gentiles is fulfilled, and God will then remove Israel's collective blindness, send two witnesses/prophets, will use the Hebrew Scripture to show Israel this Jesus was truly their long-awaited Messiah, Redeemer, Savior, anand that d King.
And then all Israel shall be saved as per covenant and prophecy. God will at that time continue building His Church up to the day of His return.
Also, you never mention how Hellenized Diaspora Jews were God's Elect to be the first fruits of the Apostles' mission to the Greek speaking people of the Eastern Roman Empire. As such, the Greek OT (LXX) was vital in God's Election to spread Christianity throughout the Empire.