I understand your argument regarding certain things being derivative but that argument only goes so far. Consider the following:This is hard for moderns, but if a king or pharaoh had a son and he gave the signet ring to him and sent him into the land, people would rightly bow down and pay honor to that prince - but, it was derivative, and the real object was the authority of the pharoah/king that was being worshipped. If someone explicitly were to say the prince was a part of a ruling "pair" and not recognize this as derivative, that person likely would be put to death (and likely the prince for encouraging or permitting it). So, this is shaky ground, I think.
4. Then they set out from Mount Hor by the way of the Red Sea, to go around the land of Edom; and the people became impatient because of the journey. 5. So the people spoke against God (Elohim) and Moses: “Why have you brought us up from Egypt to die in the wilderness? For there is no food and no water, and we are disgusted with this miserable food.” 6. Then the Lord (YHWH) sent fiery serpents among the people and they bit the people, so that many people of Israel died. 7. So the people came to Moses and said, “We have sinned, because we have spoken against the Lord (YHWH) and against you; intercede with the Lord (YHWH), that He will remove the serpents from us.” And Moses interceded for the people. 8. Then the Lord (YHWH) said to Moses, “Make a fiery serpent, and put it on a flag pole; and it shall come about, that everyone who is bitten, and looks at it, will live.” 9. So Moses made a bronze serpent and put it on the flag pole; and it came about, that if a serpent bit someone, and he looked at the bronze serpent, he lived.
In Numbers we are informed That Jehovah was offended. In 1 Corinthians we are informed by Paul it was Christ:
1 Corinthians 10:9
New American Standard Bible
9. Nor are we to put the Lord (Christos) to the test, as some of them did, and were killed by the snakes.
How is this to be explained? In the OT story God is offended. Paul says the offense was against Christ. He had just informed the Corinthians that Christ was the "rock" that followed the Israelites in the desert. Easily explained by the Trinitarian; I don't see how the Unitarian can explain it.