Coming from Oracle Service Cloud, I'm surprised how few options there are for controlling search results. Sometimes you want to prioritize important articles that contain similar key words, or you want a customer to read an introductory article first before they move on to other articles through links. Two key features that are missing that helped us do this in oracle are:

1.We were able to assign an article to show in the top results regardless of how well it matched the keyword search

2.We were able to hide articles from the internal search so that the only way to reach them would be a link from another article.

This allowed us a degree of control as to which order our customers viewed articles. The straight up keyword search in Microsoft performs far worse than what I had before despite many hours of keyword stuffing.