I agree we are not tied to the LXX. It is still interesting that John uses it to quote Isaiah 53, but that proves nothing. The point, however, is that the LXX does not allow your interpretation while the Hebrew does not dictate it.
Again, there is nothing that you've demonstrated about the LXX and how it presents the passage, nor the Hebrew, I might add. You've made the assertion, but you've not defended it.
As for my interpretation of v. 10, I'll state it again: I do not think God delights in crushing the Servant, but finds delight in the Servant's sacrifice. But, the meaning of that sacrifice is not left to our imagination.
Isaiah 53:4-6 clearly tells us that the servant bears our sin and suffers for them. Isaiah makes this abundantly clear.
I take my understanding of v. 10 from Dr. Peter Gentry, one of my professors in Seminary, who is one of the foremost linguistic scholars in the world. He says: Here “delighted” is being used in the context of a sacrifice. God is delighted or pleased with the sacrifice in the sense that he accepts it as sufficient to wipe away his indignation, his offense and his outrage at our sin." (Gentry, Peter. “The Atonement in Isaiah’s FourthServant Song (Isaiah 52:13-53:12).”
SBJT, 11/2 (2007). 20-47. But, in the article, he has already said about the passage (specifically vs. 4-6) "Verse 4 shows that the general population considered him to be punished by God for his own crimes and misdemeanors, but instead, he was paying the penalty of the sins of the people in their place, as a substitute for them" and "This is a perfect picture of the suffering servant. The Lord laid on him the iniquity of us all so that we might go free." (ibid.).
Of course, other passages tell us that, essentially, God kills Jesus. Even the Acts 2 passage you cite often tells us that Jesus was "delivered up according to the definite plan and foreknowledge of God."
At a minimum Isaiah 53:10 states the same as Peter's sermon in Acts 2 (that it was God's will to crush him". I am taking the interpretation at this point (not adding to it "by pouring upon Christ His wrath). In this vein I agree with the LXX (and, coincidentally, the early church). So you could say I am influenced by the LXX, the early church writings, and passages of Scripture denying God could have been wrathful to the Righteous. Guess you could say I'm a minimalist.
The problem, though, is that Peter quoting Isaiah 53:10 does not negate the context of the entire passage. It is still understood by Peter (and others) that Christ is bearing our sins. Certainly that's what Paul intends to convey in Romans 3.
Gentry summarizes things quite well:
The “atonement theory”—to employ an anachronistic term—provided by Isaiah’s depiction of the work of the Servant in the Fourth Servant Song is multi faceted and variegated. The Servant is a figure both Davidic and royal. He is Israel and he restores Israel (Isa 49:5). He endures enormous suffering as evil is heaped upon him by his own people and by the world. But the description is more specific than this generality. He dies as a restitution sacrifice to pay the penalty for the offenses, sins, and transgressions of the many. This brings the forgiveness of sins and a right relationship to God. This brings reconciliation with God resulting in a new, ever lasting covenant of peace where faithful loyal love and obedience are maintained in our relationship to God. This also brings redemption in that just as the Exodus delivered Israel from years of slavery to Egypt, so the new Exodus delivers the many from bondage to sin. The Servant is not only the sacrifice, he is also the priest (also clearly expressedin Jer 30:21). He makes the offering. Moreover, he is a super-High Priest. The High Priest sprinkles only Israel, but this priest sprinkles the nations who are also included in the many. His ultimate anointing leads to an ultimate sprinkling on an ultimate day of atonement! And as King, the Servant fights the battle for his people and wins. He conquers not only their sin, but death itself. The many share in the victory of the one just as the one has borne the sins of the many. The broken Mosaic Covenant is replaced by a New Covenant in which all the promises of the Abrahamic and Davidic Covenants come to fruition and fulfillment. The Servant does for the nation what it could not do for itself and at the same time brings blessing to all the nations. (Gentry, SBJT, 43).
The Archangel
God was redeeming mankind. Christ was made sin for us (2 Corinthians 5:21) and a curse for us (Galatians 3:13). He experienced the punishment for sin that was due to us. 'The punishment that brought us peace was upon Him' (Isaiah 53:5).