It’s a good thing that the previous expansion, Legion, was the best in the game’s history because Battle for Azeroth is coasting on its success. The major class redesigns that happened then remain in effect (though some are a little worse, and some a little better), and the combination of World Quests and Mythic+ dungeons means there’s always something to do, no matter your skill level or how long you can play.
Meanwhile, on the island continents introduced in the Battle for Azeroth expansion, players level 110 and above who have unlocked world quests can participate in Faction Assaults. These special events, alternating between Alliance and Horde territory, will give each faction a chance to band together to defend their territory or invade their enemy’s via a series of world quests. The prize? Survival! Also faction, gear and gold. Maybe even some pride.
Inscription – This one deserves its own category. I recently got back into this profession and I think it can make some serious gold at all levels due to how glyphs work now. On the flip side, glyphs are cosmetic one time uses only and the market can be really slow for the less interesting ones. I also recently installed TSM and I think you need some kind of addon like this to manage your production and sales if you are going to be in the glyph market. BfA is also keeping the tomes and adding in new reputation contracts so that could also provide a steady income.
-PvP- Completely broken for some classes and I mean broken going from both sides of the spectrum, from classes destroying everyone, to classes that can't even kill another player. It's fairly common for a weak class to lose to a powerful class even if the weak class outgears them by 50+ ilvls. That's how broken PvP is and Blizzard doesn't seem to know what to do to fix it other than do blanket damage nerfs/buffs as those are the only changes we've seen.
The world quests aren’t necessarily bad, but they aren’t good either. I wouldn’t mind killing five of a type of monster or fighting one particular boss a few times, but after seven or eight, it starts to wear pretty thin. But going from levels in the mid-20s can take nearly 30,000 AP, so you’ll need more than world quests if you want to get your heart up in a reasonable time.
So much new stuff. The war questline expands. Island expeditions get a couple of new locations to explore. Azerite armor gets tweaked so it’s slightly less stupid than it already is. While we wait for the servers to go back up, Blizzard’s prepared a handy survival guide for Tides of Vengeance. I suggest looking it over, or else risk not surviving at all.
Inscription and darkmoon decks remain highly profitable still as long as you approach it with the right mindset and understand that it is a commodity market and the goal is not necessary to sell crafted decks. For me, it's an exercise in managing purchasing Linen & Herbs below market, balancing opportunity cost of converting linen to expulsom, and mass purchasing underpriced individual cards and relisting them at a profit but under the crafting cost so that they move. That's the primary goal, and you naturally complete decks that you sell but you don't go out of your way for.
Enchanting, Jewelcrafing and Alchemy are also good quality choices no matter what the expansion is because potions, elixirs, flasks they are always needed which made by Alchemists. Then we have enchanting pretty much the exact same thing with alchemy. There is no expansion where people would not need enchants. Then we have jewelcrafting once again same thing, stat gems which always go for a fair price in Auction House. Also this profession synergizes with mining and making good profit by only purchase and prospecting ores.
Sky golem is all profit if you do the smart thing and run old panda farms on multiple toons. Was running 10 farms at one point till bfa launched and was upto my eyeballs in trillium and Ghost iron. Just not been doing it lately, but those 10 farms was an hour a day if that and sustained 4 crafters and alchemists though could have sustained 8 easily.