Next, Enormous amount of mats? 4200 Ghost Iron Ore. That's it. Look at Depleted Kyparium Rocket or Turbo-charged Flying machine or the mechanohog, all have more complex recipes with mats requiring you to go to a vendor to get. Let's be honest I bought a bunch of Hula dolls because who wants to go to Shattrath anyway but c'mon. What you're saying is just not true. Its simple, its quick, and the procs aren't random (I transmuted 100 Trillium bars last night and got 122 bars). Most people don't need the procs, but optimizing allows you to make more gold, and ultimately this is a goldmaking subreddit. If you don't want to follow the advice, don't join that market.
I think what you're actually talking about when you say "niche" is the barrier to entry for new players. It sounds like you're worried that new players can pick up crafting professions and compete easier than before. Again, I'd say that the alpha build info in the OP looks pretty much the same as the current expansion. The true barrier to entry isn't the ability to level the profession quickly, it's actually recipe ranks. Some really good examples of this in the current expansion are rank 3 bracers, rank 3 flasks, and rank 3 felwort. It takes a certain level of investment to get those ranks, and the goblin activities related to those crafts simply aren't profitable/competitive without rank 3.
Your paying top dollar for these plugs, I'm sure you've done your homework. I believe that Audioquest does make good products but they do come at a cost. I built a few cables using these connectors and was a bit disappointed that when using Audioquest X2 cable and stripping the right amount only one of the screws seemed to hold the cable in place. I had this experience on 16 of these banana plug.
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. :(
"There will be some story-driven quest content, world quests, with a bit of catch-up gear, telling the story of the Horde incursion into the night elven lands, that will lead up to the actual burning of Teldrassil," he said. "We want to be sure we’re actually telling that story in the game. That’s going to be our pre-launch event that unfolds over the course of a week and a half or so. That will be available to everyone who’s playing World of Warcraft, regardless of whether you own BfA or not.