This is a useful definition of inerrancy:
"The inerrancy of Scripture means that Scripture in the original manuscripts does not affirm anything that is contrary to fact" (Wayne Grudem, Systematic Theology, page 90).
Quoted from this very helpful article: http://www.fivesolas.com/inerrancy.htm
As the above article makes clear, fumbling around with an imprecise definition for inerrancy is sure to lead to trouble.
For example, when I started reading Scripture as a young man, I was confronted with many of the things to which you now appeal as evidence of factual error. But unwilling to accept a superficial verdict, I dug beneath the surface and found and continue to find rational solutions for these passages I presumed (in my youthful hubris) to be problematic, largely because I was guilty of imposing my own flimsy definition of "inerrant" on God's word. After many years now, and seeing many of those objections as they are raised by atheist and Islamic partisans, I have yet to find one that is unresolvable, either by simply increasing my knowledge of the circumstances or language, or by identifying issues with genre, style, culture, etc., that make it clear the Scriptures were affirming true facts after all, despite my initial misunderstanding.
And that gets down to one of the main issues. What are my assumptions going in? If I accept that God by definition is capable of reaching His people with His message, then I am going to be looking for a message that is divine in quality and nature. I expect God to tell me the truth. No, I do not expect that I, in my fallen and limited humanity, will by purely naturalistic means be able to understand everything He is saying to me. But God's arm is not so short it cannot save. If He wants me to get the memo,
I will get the memo. I might not respond to it the way I should, but I will know what He wanted me to know. If God could not accomplish that tiny, easy, little task, it would impugn His power as God. God, to be God, must be able to speak to us.
As for the litany of supposed problematic issues, virtually everything you recited has relatively easy solutions. For one thing, raising the Old Covenant as though we are being inconsistent if we don't reactivate it is rather like saying that because America started with 13 colonies, we aren't true Americans if we don't get back to the original 13 colonies. There is universal, unchanging truth, but it is contained in a history of movement and change. Progression through time and events do not
change universal truth; they
illustrate it.
For example, the OT/NT relationship is best understood as the systematic unfolding of God's eternal plan of redemption in time. Every step of the process was essential to get to the next step, but no individual step so far represents the end state of the process. So we have God making a covenant with Abraham, which we learn from Paul comes to fruition in the appearance of the Messiah for all people, not just Israel. Yet God's dealings with Israel, and His specific covenant with them, are essential to fulfill God's promise to Abraham. And then, when Messiah does finally come, we learn from Him and His apostles what the New Covenant will look like, though it has been predicted in the Old, and in fact that prophesy used to validate the New.
So you see, viewed as a self-consistent but sequential system, we would be in
violation of the revelation to resurrect the Old Covenant where it has been explicitly set aside by the Maker of the Covenants. What you appear to be suggesting, by contrast, is more like a multi-stage construction contract, where we finished the foundation, and now new rates and rules apply, by agreement, and you seem to want us to violate the contract by going back under rules and rates that no longer apply to where we really are in the project. You are in fact advocating that unless we breach the contract, we aren't really keeping the contract. Do you see how this might strike us as irrational?
As for the argument for a kind of universalism based on uncertainty, which is how I read your core argument, I don't think your premise is valid. Based on what you have written, you appear to be arguing that superstition is OK as long as it leads to people trying to be good, but that any attempt to come up with a sound definition of what is good is "heretic hunting." The underlying premise in that mess is that God has not objectively revealed truth to us that we can use to know how to relate to him, so it's OK to just make it up as we go along. In which case we are no better off than the secular postmodernists who disavow any notion of being able to know universal truth, other than the single premise that there is no universal truth to be known. And if you have in fact accepted that fatally circular epistemology, I can see why that premise of uncertainty about God's message would make sense to you.
But we do not accept that God's truth cannot be known, because we do not accept the reductionist view of God it takes to get there:
For as the rain cometh down, and the snow from heaven, and returneth not thither, but watereth the earth, and maketh it bring forth and bud, that it may give seed to the sower, and bread to the eater: So shall my word be that goeth forth out of my mouth: it shall not return unto me void, but it shall accomplish that which I please, and it shall prosper in the thing whereto I sent it.
(Isaiah 55:10-11)
Peace,
SR