Andrew, I think you are being very selective in your interpretation of this passage, and in your summary (‘the prototypical narrative pattern’) of Isaiah.
Paul is addressing Jews and Gentile God-fearers (Acts 13:26), who were familiar with the scriptures, and would want to know how Jesus related to the history of Israel. That is the point of Paul’s summary of Israel’s history. Jesus came in the context of a history of a people through whom the coming of the Messiah had been foretold.
At the key point in the address, unremarked on in your commentary, Paul declares what kind of Messiah Jesus came to be. In verse 38 - “through Jesus forgiveness of sins is proclaimed to you”. This entailed not only restoration of blessing to believing Israel, but the reversal of the fallen state of creation prefigured by Isaiah, and demonstrated in the ministry of Jesus towards the poor, sick, lame, blind, deaf, demonised and dead (and continues to be so). At the centre of forgiveness of sins is the death of the Messiah on the cross - “This is my blood of the covenant, poured out for many for the forgiveness of sins” - Matthew 26:28”, and his resurrection from the dead.
Paul also declares, at this key point (verses 38-39), unremarked on by your commentary, “Through him everyone who believes is justified from everything you could not be justified from by the law of Moses” - verse 39.
The quotation from Habakkuk which immediately follows suggests that forgiveness of sins and justification would take place in a similar time of trouble, and warns of what will happen to those who reject this justification.
The reference to justification is particularly important, because it provides a meaning which goes beyond the definition as a boundary marker, as in Wright and the NPP’s view of justification. It includes the act of forgiveness and absolution from “all things” for which the law of Moses had failed to provide absolution. It was not simply the identification and declaration of righteousness. This is not to say that Wright or NPP are wrong, but that justification must have a broader semantic range than they have assigned it.
It is to this climax of Paul’s peroration that “the Jews and the devout converts to Judaism” respond (verse 43), to a declaration of sins forgiven (in the broad meaning of the term), demonstrated in the life, death and resurrection of Jesus, which had not previously occurred in Israel’s history.
We see in the passage the significant discontinuity brought by Jesus into Israel’s history, as well as the unique way in which Jesus as Messiah addressed Israel’s history. Jesus did what the law of Moses failed to do, because it could not do.
The Gentiles referred to in verses 16-41 are “devout converts to Judaism”. Subsequently, when Paul addresses a crowd of Gentiles from the whole city, he responds to Jewish agitators among them by offering the Gentiles the very salvation (verse 47) of forgiveness of sins and justification which the Jewish agitators reject.
Am I wrong in saying you have omitted this section (Acts 13:38-39) from your commentary? I think it is the key to the whole passage.