So, the gentiles are grafted into the same root as the Jews. They become part of the same vine. They are not a "separate" vine, but part of the same vine (i.e. the children of promise).
That's right grafted in with the believing Jews. We also have the broken off Jews or the unbelieving Jews.
And I notice you didn't address the passage from Eph. which clearly states that the Jews and the gentiles have become one new man in Christ because of His work on the cross, and that they will now be presented to God as one body.
Again that is correct the believing Jews and the believing Gentiles are one. Not the unbelieving Jews. In the past you had to become a Jew because salvation was of the Jews. Now we have access to God without the Jews.
I don't see any mention of a separate future for the Jews in that passage.
peace to youraying:
And it is not necessary to be in this particular passage.