Stormheim is the zone you want to start it. For some reason Legion treasures are not worth any experience like they are in WoD...except in Stormheim. I haven't been able to find out any reason for this, and it's possible it may get fixed/nerfed at a later date. But for the time being you REALLY want to jump from treasure to treasure to augment your quest experience.
Special note: At 110 it's almost certainly worthwhile to go and immediately get your Heart of Azeroth and first piece of Azerite gear from the BfA opening quest. It doesn't take long and provides pretty high power levels. I'd then return to Legion quests until 111 or even 112, since the power of these items will increase your kill speed significantly over the scaled enemies of BfA content.
5% was admittedly an exaggeration, just felt that low. I'd say it was probably closer to the 30-40% range. It was Artifacts of the Blacksilt, spent a good 10-15 minutes killing Blacksilt Seers to get two damn idols to drop. A quest that had me killing Elder Brown Bears for bear flanks also took quite a while, though that was less due to drop rate and more due to how spread out they were.
The zones in Battle for Azeroth are littered with treasures and rare spawns that give the same amount of XP as quests. With Zygor's Leveling guide these points of interest are displayed directly on your map and can be clicked at anytime to add them underneath your current guide step. The guide will then switch focus to the POI, direct you to its completion, and tell you how to complete it.
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A: The WoW Token feature is designed to facilitate the exchange of gold and game time between players in as secure, convenient, and fair a way as possible, and without making players feel like they’re playing a game with their hard-earned money. Having a set current market price and a straightforward exchange system is the best way to achieve that—you don’t need to worry about whether your Token will sell or not due to being undercut or the market shifting, and everyone receives exactly the amount of gold they were quoted.
If you already have a high-level character and want to quickly level up a new one, by far the best tools for the job are the items labeled “heirloom gear.” These pieces of gear have two very special properties — they bind to your account, so any character you own can use them, and they grant bonus experience. Their stats also scale with your character’s level up to a certain point, so you can equip a fresh character with heirloom gear and power through much of the game.
Once characters reach the level cap, gameplay turns from leveling to the end-game. This represents the culmination of the leveling process and the beginning of the deeper challenges awaiting max-level characters. While play prior to this point is oriented around accumulating experience and gaining new skills, the end-game represents the polished 'final destination' for players, at which characters are fully developed and ready to tackle the biggest challenges in the game, or to relax and make their own adventure.
Also note that power leveling is sometimes used to refer to paying someone else to level your character to cap as fast as possible (i.e. they power level for you); a distinction used by Blizzard is to refer to the paid leveling as "power leveling service." This behavior is against Blizzard's Terms of Service. Power leveling yourself, which this article covers, is perfectly acceptable.
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The leveling guides on my site are essentially speed leveling guides.  My leveling guides are the same guides I use myself to speedrun to 60 on new servers to get 60 server first.  I list many occasions where I tell the player to "die on purpose" to go faster.  I tell the player to skip certain quests, because some quests are just not worth the time/XP.  I list tricks and shortcuts to go faster so you can reach level 60 much quicker.  I am still constantly going through them over and over again perfecting the guides to make them faster and easier to follow.  For the most part, the guide can be followed without the need from other player's help, as the whole guide was made from a solo run anyways.  Although I do list quests that can optionally be done if you have a group.

The additional recipe ranks can be obtained either by exploring the outdoor Broken Isles zones or as rewards when you dive into the dungeons of the region. If you’re feeling up to the challenge, you can aim to hit skill level 100 and player level 100 to open up profession world quests, which rewards higher rank recipes for your Legion gold making operation.
Incorporating an accelerated leveling pace is *definitely* something we want to incorporate in to the new addon My hope is to allow an option for you to set yourself to one or two higher speeds, where the guide will skip some steps along the way. The steps will have a special tag that lets the addon know to skip them if the person has that setting enabled.

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.

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