I found few interesting links while doing some research on the hype of google search algorithm. Here is part 1 of it.
Following the above formula we can begin constructing our questions and possibly get closer to the 200 questions google claims their algorithm asks. The following is a list of questions I think may be involved in the process.
If you want to build a better search engine, the problem is to change what is meant by search. I think the future holds a better solution than what we have today. Returning a list of pages is not a very modern way to search. The only reason Google still does it that way is because they found a way to make money selling ads next to search results. Organic search results are just there to sell advertising. It would be an interesting project to create an open source search engine, and ELW is already on the case.
Once you have identified these basic SEO metrics, you can then determine if you need to (a) create more pages (b) go back to legacy content to add additional keyword modifiers to related pages using the site:yourdomain.com keyword command (c) acquire additional inbound links or (d) focus on conversion optimization based on which keywords have the highest engagement and conversion.