"Jesus Died For Us". In what sense is this true, in what senses is it false?

I am re-watching a 2015 TV series AD: The Bible continues; which is supposed to be a dramatization of ("based on") the Book of Acts I had seen when it came out. It is pretty enjoyable in a melodramatic way. and worth a look - a reasonably sincere production; if you are not too concerned about embellishments and looseness. I am also reading Taliesin by Stephen Lawler (1987). 

In both of these (as well as many other places, over the years) I came across the often spoken phrase that  "Jesus Died For Us" - used with a variety of meaning, some of which I personally would regard as untrue, and potentially harmfully-misleading.

So in what sense is "Jesus Died For Us" true, and what senses do I regard it as false? 

1. Overall, I would say that it is untrue; in the sense that Jesus died because he had to die, because he was mortal. 

Jesus could-not not have died.  

So if the phrase is meant, or taken, to imply that Jesus might never have died at all, ever - then this is false. 

2. Sometime the phrase is used to mean that Jesus could have saved himself from being killed at the time he was killed, or in the manner he was killed. 

This is true; he could have saved-himself from that particular death - albeit Jesus would have died some time later, and/or in some other fashion. 

3. Sometimes the phrase is used to assert that it was necessary that Jesus died in the time and manner that he did; or else Jesus would not have succeeded in his mission - and Men would not have been offered the possibility of salvation. 

This I regard as false. It was Not necessary for Jesus to be tortured to death when and as he was, in order to be our Saviour. 

In sum, Jesus needed to die in order to become The Saviour, but he did not need to die when he did and by torture and crucifixion; yet he could have saved himself from that particular death.  

As usual, these surface inferences rely upon metaphysical assumptions concerning why salvation was needed, why Jesus could achieve our salvation but not God the Father; and in broad terms how salvation "works". 

Such metaphysical assumptions need to be "in place" before we can make valid sense of "Jesus Died For Us" -- and lacking such a grounding of the structure of basic reality; the phrase is likely to lead to (what I would regard) as a wrong and harmful understanding of the very fundamental nature of what it is to be-a-Christian: to follow Jesus. 

As things (mostly) are; the metaphysics and the understanding are presented the wrong way around; with the Biblical description supposedly giving us the metaphysical understanding by which it is interpreted. 

Or there is a dishonest (or incompetent) assertion of unavoidable circularity of reasoning; that (wrongly) states we must believe both the metaphysics and the Biblical description as a single, given, object-of-faith. 

The truth is that we can make no sense of anything without prior metaphysical assumptions - and these, therefore, need explicitly to be exposed as such: and set-up for evaluation.