Welcome! While this leveling guide is specifically made for the class and specialization(s) listed, we also have a general Battle for Azeroth leveling guide that focuses on the specific features of the Battle for Azeroth expansion including preparation of your mission table that will be used to unlock new areas, progressing on your faction's War Effort to save time at Level 120, and a reminder to keep ALL of the gear you find for the Scrap-o-Matic 1000 or Shred-Master Mk1, which will greatly increase your resource generating capabilities. Please visit our 110 to 120 leveling guide for this information and more (including Heirloom and War Mode advice that also applies to players who are not yet Level 110.
As Blizzard calls it stats were "squished," and now players are finding it harder to level with that same scaling system. It's a two-fold issue, and game director Ion Hazzikostas isn't quite sure how to fix it yet. In a massive forum post several days ago he plainly explains the issue from the start, noting that "the feel and pacing of the level-up experience is a top priority for the team."
Fourth: This is very important; do not vendor the gear you obtain while leveling. There is a new mechanic introduced in BFA called the Scrapper which allows you scrap your gear for trade goods which will be very important for rep and AP grinding (will talk about it more later). Usually after I clear a zone, I will head to the scrap bot and scrap all my greens/blues to clear my bag for the next zone.
Fourth: When the enemy faction controls the Warfront, you get access to 11 quests that allows you to trade materials for AP and honorbound rep. This is huge because you get 750 AP per turn in and 500 rep per turn in which gives you a total of 8250 AP and 5500 rep; that is a massive amount. All the material you got from scrapping all your leveling gear will come in handy here and I imagine that you will be able to trade other players for different turn ins. I highly recommend trying your best to do all 11. Also, this will be a great opportunity to make some serious cash for your profession because people will be buying the same items in bulk.
He goes on to say that the changes went too far, and that they have "no desire" to keep moving in that direction. The problem is they don't know how to fix it quite yet. Hazzikostas understandably says that they don't want to make blanket changes that miss the "real source of the problem," which is exacerbated at levels 60-80 when the leveling curve gets particularly punishing. The sky isn't completely falling though based on data: Hazzikostas says that leveling is 15% longer. In the short term they want to increase experience gained at these levels to soften that blow.