The Escalation patch has introduced several new scenarios with respective heroic modes that provide shiny new loot. It is still too early to predict which of these will demand the highest prices at the auction house or AH, since it can take weeks for players to work through the content and determine the value of the new drops compared to the existing items. Many expect the rarest and most prized drops to start commanding handsome prices starting June, so just keep your eyes peeled for popular WTB requests in general chat and high-selling items at the AH.
Edit 20 It’s been a week since this post and a lot of people are still reaching out to me with questions which is fine. I have had a few different people reach out to me to help make YouTube videos based off this guide and more info in BFA which I’m more than willing to do. Whoever gets the videos up first I will link them here for you guys to enjoy.