Try to include in your speculations the sequence of events. First people were complaining about the hardships of freedom expressing a desire to return to Egypt. Then people complained about the law, probably because they saw themselves on the forbidden menu. Then God sent a plague of serpents, a metaphor for a human archetype, just like a plague of gibbering and squeaking evangelicals, and people "died" when bitten and then the people complained about that. That's when God told Moses to build a statue of a serpent and tell the people to turn to that for healing.
I'm disappointed in you if you think that turning to a statue for healing wasn't wrong from the beginning, even if God said so, the same God who gave the law prohibiting such practices.
Its like Jesus whose disciples always called him Lord but never did what he said telling them "eat this" because they didn't give a **** about the fact he just told them he was about to be killed.