I think I see the problem, D-fendr.
We’re arguing based on the assumption that the Christian god is the Old Testament god that ordered 1 Samuel 15:3, and is the same as Jesus.
If this assumption is wrong, then let me know, explicitly.
It's not that it's not the same God. Scripture is inspired by, but not written by God (in Christianity). The writers of Scripture are finite humans writing within their context and knowledge. This is why you see such things as "light of the eye" instead of the correct idea of reflected light.
As I said earlier, I see the OT as it is: developed by ancient people over centuries and finally written down.
It is the way they saw, experienced and explained themselves, God and the events of the world. Sometimes, for some writers, in some circumstances, they see God this way, another time that way. Always, God as part of their lives. You pick Samuel, but ignore much of the Psalms. You denigrate and simplify unfairly, IMHO.
Our concept of "historian" or "Journalist" does not apply. To hold them to our standards is quite unfair. If we had lived back then and faced the brutality of their world, we might not be so puffed up. We sometimes claim to have passed a test we never took.
Rather than pick a chapter and tear it apart, the OT requires and deserves a great deal more study first. I spent what is, for me, a lot of hours of classwork on it, and felt I was just beginning to have enough knowledge to get the context and flow and see the differing authorship, viewpoints, conflicts, etc.
I don't think you are receptive to this, and I'd refer you to other books if you were.
Anyway.. it's the same God, but IMHO, an increasing understanding of that God. Culminating in Jesus.
Bottom line as it applies to your question: For Christians, Jesus is the model for understanding God in human terms (just/unjust, forgiving/vengeful, etc.). So if your view of God in these terms does not hold when applied to Jesus, then it is not the Christian view of God.