The idea behind SA is that throughout our lifetime we have committed sins and accumulated a "sin debt" that must be paid, and that Christ's death pays that debt. But, what practical thing would that accomplish? Would that correct the wrongs that you have done? No, the damage caused by your past sins would still remain. What's done is done. Nothing changes. Christ's death is devalued.
I know I said I wouldn't post again, but I can't help but comment on this, because again, what you are saying is flatly contradicted in the bible. Not only in the language put forth in Rom. 5:8-10 quoted above, but also in the same chapter you are quoting from Hebrews.This is why, I believe, the writer of Hebrews said that it was impossible for the blood of bulls and goats to take away sins (Heb 10:4), because the focus of that ritual was on past sins and what's done is done. But the [better] sacrifice of Chirst is about taking away sins not yet committed so that good things replace them.
Heb 9:15 And for this cause he is the mediator of the new testament, that by means of death, for the redemption of the transgressions that were under the first testament, they which are called might receive the promise of eternal inheritance.
.However, if Christ's death serves to change your life so that you put away your sinfulness, if it brings about repentance and new birth, if it causes you to be a blessing to others, if it brings peace and joy in your heart, then it has great meaning and accomplishes great things
His death does this too (see 1Pet. 2:24; Gal. 2:20-where both ideas are present), but that's clearly not all. You are interpreting all of the passages with this paradigm and it just doesn't work biblically! You have simply ignored all of the relevant texts, and asserted that they can be interpreted another way. Well...How?