You can see why its confusing though surely and why some, like myself, really see God more in terms of a creator/destroyer because thats certainly how he is portrayed in the OT
This is the corruption that modernist theology has brought even into the evangelical church. Modernist theology devalues man to something less than being created in the image of God. What God told Moses to write in the Law was that it was because man is made in the image of God and therefore unique among all the rest of creation, that He sets such a high value on man (male and female) that taking a human life is one of the absolute biggies in His mind, and therefore He was, and still is, very strict and unbending about His judgment concerning the deliberate taking of another human life. When war is mentioned, there are many who conscientiously object on this basis. I would if I were younger and faced with having to go to war and take human life. I couldn't do it. Yet, it was allowed at different stages in the Old Testament, and this is explained in the Scriptural text.
We can see in the case of Achan, that the man was stoned along with his whole family. Our modernist mind sees that as cruel and unjust, but the explanation was that in order for the Jews to continue having victory, the corruption of sin had to be removed from the people. When God moves in judgment and takes human life there is always a very good reason for it. Usually it is because of unredeemable evil. Yet in the midst of all that, Rahab and the Gibeonites found mercy when they turned to the God of Israel.
If you read the Scripture carefully, you will see that there is no one who has genuinely turned to the Lord who has been killed. We have to understand that God's ways are not our ways, and everyone who died in the Old Testament died for good reason which is explained. People who see God as just a cruel creator and destroyer, have not read the Old Testament very carefully and have made uninformed judgments about God and why He has allowed to happen.
But the completion of the revelation about God came in the Person of Jesus. Jesus came to show us what God was really like and that His death and resurrection ushered in a whole new way of approaching God and having the type of fellowship with Him that Adam and Eve had before the Fall.
We must remember that death is not the end of everything, and all those who died, still existed in the invisible world, waiting either for full salvation which they looked ahead for the work of the Messiah, or to appear in the final judgment when their works will be evaluated before God.
The modernist sees death as the tragic end of everything, because to him man is just a bag of chemicals, a machine, the result of time and chance, and not one made in the image of God.
I think that understanding this can assist us to see how absolutely evil abortion is, where unborn babies are denied a chance to life because of the selfishness of others.