Neither the Hebrew nor the OT Commandments were written with salvation or a world to come. There was a hint of a world to come in Isaiah but the life after death, sin, and salvation were all invented by Paul. The Decalogue is simply a sacred rulebook as you note.
I do find it interesting that in the Hebrew Decalogue the social rules are mashed into 2 verses. In your version the 10 could be contained in 3. 1 through 8 condensed into ""These are our highest most honesty-keeping rules and should be considered sacred." I can see where Hillel the Elder got his one foot Torah. And Jesus found his Two Commandments: 1-8 condensed into Love the Lord thy God, and the rules condensed into Love thy neighbor as thyself.
I know why my Jewish friends liked to talk about Hillel the Elder. I didn't really notice that God was missing from our discussions. I have no doubt that God was assumed by Hillel and my friends as the originator of the social rules, but the overemphasis on worship and obedience to "I am the Lord Thy God" was clearly missing. No wonder atheism is compatible with Judaism. If the rules, all 613 of them were the result of a tradition that worked there is no reason to add God to the tradition except to establish a supernatural cop that would punish transgressors. Moses was for some reason having trouble governing his tribe, and perhaps thought that a supernatural supercop was just the thing he needed. It sure did work. A few thousand years of working.