The hexweave bags are still a safe bet unless the new 32 crafting cost is like 10% of them. The one thing I'm more concerned about is the professions squish. This will make the old world items that we've been selling (TBC Dust still sells by 200 stacks easily) only required for Transmog and not leveling. This was a better option for a lot of professions (especially enchanting). Expecting their near-death with the next expansion. :(
2. Island Expeditions. What?! you may ask, but it is simple. The transmog that drops, now rather frequently, from the expeditions sells well and for high amounts. Despite its somewhat common drop rate the fact that the loot table is so large means that people seeking certain transmog will be more likely to buy it than farm it. The parroted meme on r/wow that it is unrewarding only makes it better for someone like me. In the past two days from doing Island Expeditions on the side (about 20 total) I got 6 transmog items of TSM values between 15k and 150k. I sold 3 so far totaling 140k (Plundered Squid Caster: 50k because I wanted to be rid of it, Stinkrot Smasher: 69k, Razorfin Breastplate: 28k). Pet drops are a different story and while you can sell them, the fact that they need to be looted for the achievement means that the potential buyer pool is smaller.
Rank 3 is terrible design, if they we're most open about how they drop etc. I, as a avid LW collector (Yes I have all recipes in-game but IIRC 1 from vanilla, few from TBC that was removed due to stupid design), and I still dont have all rank3 from LW despite plenty of runs through the 5 mans for em...Ill just wait for next exp or w/e and stealth runs.

Crafting (Blacksmithing, Tailoring, Leatherworking) – When it comes to endgame, I always found crafting to be very dependent on the level of gear you can produce. There have been times when the crafted gear was competitive with the gear you could get in the open world and during those times I always had success. Then there are the dead times when the game gear vastly out levels anything you can craft. There still is time before BfA launch for the devs to make more changes, so I am not sure where crafting is going to come out this time. Whatever they do, I have always made some gold selling transmog and Blacksmithing has shined in this area for me. Many folks don’t take the time to collect old rare recipes which can leave few competitors. Transmog never sells fast, but it can work.
All of my gold came from everyone buying stuff at a really marked up price for instance BS 2h mace if it proced epic i was making at least 125k per one and i was making batchs of 10 to 15 it was like 25k for blue and 125k+ for epics at the time. And i was buying the ore for like 16g to 40g a pop so huge profit. Im still trying to figure out what im gunna do now to rebuild it will be a slow process now.