I'd check misspelling. American vs British. Plurals. Non Dictionary words. Small words. Names. Initials. Exact match. So, quantifiable stuff. Then prescriptive

I'd check misspelling. American vs British. Plurals. Non Dictionary words. Small words. Names. Initials. Exact match. So, quantifiable stuff. Then prescriptive. The idea would be a framework so someone can make (or grab their current data) the test different engines for different search terms against the data and mark which is correct or better. You don't have to 100% agree what search result is better. But to just get to the stage where you can discuss that would be a great start. And I suspect not agreeing what is better is not as contentious as one thinks. I also think Google does search real well. So use that for a set point of the truth.