If the new Battle.net balance has given rich players a new incentive to liquidate, and the spiking prices are a result of them trying to sell all their gold at once? Prices for tokens could settle much lower once that stash of gold has been depleted. This seems likely, because there’s a compelling new reason to sell gold, but no new reason to buy it. Blizzard has a good way to drain those gold reserves from the market.
Congratulations on reaching Level 120! There are a myriad of new things to do. The first thing you should do is head to your faction hub ship where you have been doing your mission table quests and footholds to pick up and complete the quests necessary to unlock World Quests. World Quests will provide you an opportunity to grind reputation levels, acquire gear, and gather Azerite. There are tons of new things to do that we will cover in our Level 120 Battle Guide found here: Level 120 Battle Guide
Leveling in WoW is pretty linear and easy compared to most other Mmorpgs, and the in game quest mechanics makes the leveling process pretty fast. Our WoW Leveling Guide is the best and quickest free leveling guide for WoW. Just start in your race starting zone and make your way to new level appropriate zones as you level up. This guide won’t go in depth on exactly what quest to do when, but you really don’t need anything like that in WoW anymore. However it will take you through leveling all the way from level 1 to level 90. From Classic WoW, Through the Burning Crusade, Wrath of the Lich King, Cataclysm and Mists of Pandaria.
To give you some perspective I leveled both a LF Ret Paladin and BE Rogue (so one started from level 20 and the other from level 1). I focused on getting the achievements I was missing for the Loremaster, so not the most efficient route by any means. I was using full enchanted heirlooms (minus the ring) and the WoW-Pro addon though, as well as having War Mode turned on all the way.

In addition to questing and running dungeons in the Broken Isles, players should also remember to visit their class hall, which is like the garrisons from Draenor, but themed around your character’s class.The quest lines in your hall provide valuable experience and open up important features, like artifact weapon upgrades, that will drastically up your character’s power.
In Legion, some of the dungeons include the Black Rook Hold, a max-level dungeon in Val’Sharah that once served as an elven fortress but has been corrupted by a malevolent force. If you decide to quest in Stormheim, you can also try to clear the Halls of Valor, which lets you take on the Vrykul God-King and vanquish the pure Val’kyr that are superior to those found in Northrend.

At Level 78, you unlock the stat Mastery, which increases your Shadow damage. When you unlock this stat you should switch your level 56 talent from All Will Serve to Clawing Shadows, as it benefits more from the Mastery. The mechanical change when using Clawing Shadows is that you will be able to pop Festering Wounds from a distance. If you want to attack multiple targets with Clawing Shadows using Death and Decay's cleave effect, make sure you play the Death and Decay below your own feet instead of the target.

There are various upsides to this imbalance. Max level players are able to complete lower level content with ease, allowing them to swiftly complete missed quests and achievements in earlier zones, and can travel through zones without being constantly attacked, since mobs will only attack players several levels higher than them if walked directly into. Max level also makes it possible to solo earlier group content such as dungeons and even raids, making farming loot such as mounts far easier, and for those interested in a challenge opening up a new subtype of play at slightly higher levels.

Usually it's best to avoid a lot of instance runs. It is too difficult to account for bad groups, and some instances are too far away with too few quests. Since the experience is very good, it's a good idea to clear nearby instances which have a lot of quests once (Gnomeregan, Deadmines for Alliance). Distant instances with few quests should be avoided (Deadmines for Horde). Low level instances can be cleared by paying or befriending a single high level character. However, since patch 3.3 a new Dungeon group finding system has been implemented, as well as a direct port to dungeons (when entering the group you get ported to the dungeon and back to the same location if you leave it) and thus the travel time to dungeons has been greatly reduced. This makes it a good idea to complete quests or grind while you wait for a group to become available.
Something to keep in mind as well is that this will make enchanting materials more valuable, since it is likely most players will now simply scrap their boe greens instead of getting them disenchanted. Also redundant dungeon/raid gear can be scrapped rather than traded to the (guild) enchanter in the run. Less stuff gets disenchanted, meaning there will be less ecnhanting materials, meaning their value will rise. All the more reason to DE rather than scrap as an ecnhanter.