The OP wrote:

An example of this is the "inverted pyramid" structure for many news articles - start with the salient facts, then the most important details, then fill in the other details.

Ugh! The vomitous mass of facts and details. I can't stand articles like that. A little quote starts ringing through my mind "When you talk like this, I can't help but wonder, do you have a point?"

(1) explain what it is about, why it is important, and what others have done.

This is closer to what I would advise.

Start with motivating the reader by identifying a known problem and your contribution to the solution for it. Let him know what's in the pot of gold at the end of the rainbow, so that he might want to get there.

Up front, tell him the payoff of reading the paper. Then he might be motivated to continue reading.

Then describe the path you'll be taking him, so that he can track the progress to that pot of gold.

The path should include a formulation of problem, a description of current approaches, a description of your own approach, a comparison of the basic approaches of each, a comparison of the performance of each, and a summary of what was found in the pot of gold and how we found it.

The history of the problem and it's solutions are something you might add in a longer paper.

I can't stand articles that leave me wondering where they're going and why. It goes beyond motivating with a payoff to simply being able to follow what is being presented. If I don't know where we're going and why, it's very hard for me to follow and evaluate the paper. If you're not going to give me a map, at least identify a purpose.