Kul Tiran human (8.1.5) - "Kul Tiras was founded by fearless explorers who sailed uncharted waters in search of adventure. As a key member of the Alliance of Lordaeron, the Kul Tiran navy dominated the seas of Azeroth with its legendary fleet. But after years of turmoil and hardship, the kingdom grew isolated and vulnerable to dark influences. Thanks to the help of brave heroes, House Proudmoore has been restored and Kul Tiras is poised to fight alongside the valiant Alliance once more."
All I know is that Scribes are going to make bank with those Contracts. All guides talks about them and everyone will want them. Better ride that money wave while we can. Other than that, Alchemy and Jewelcrafting are always safe bets with tradable and marketable goods. Engineers can get an item for followers to bring back more Azerite, ot sure how much of a headstart that's gonna give them. The rest of the professions honestly looks kinda lame since most of everything is BoP anyway.
It is really, really a stark change of pace from WoD and Legion where just questing and killing things would result in at least a small but decent profit from a day's activities, typically of at least 1k and often 2k. But now to get that sort of return, I have to really focus on gold WQ's, not spend any money on anything that I don't absolutely have to, and do 45 minutes of Legion content.
I think that's server dependant. I make a lot of Golems, but the price on my server is high enough that you could buy all the living steel and still make about 20K (almost 200kg on AH). Its just that you proc all the way up the chain. You proc 20% of your trillium, and then 20% of your living steel. SoH and Ghost Iron are such low effort farms, too. 20% of 180 Trillium Bars at 500g is 18k more profit, 20% of 150 Living Steel at 3500g is another 105kg. That's an extra 25k profit per Golem. If they stop selling stockpile them for the next expansion, they always boom with the price of herbs. And a consistent 20% proc rate is the opposite of RNG, its extra free stuff as a benefit to completing an extra quest (not to mention for new alchemists the investment of leveling Vanilla Alchemy). You're looking for some get rich quick scheme, where the real way to build wealth is patience and volume. No market is going to be viable because you want it to be. Only because you make it viable.