This gold making advice is applicable to most players, except if you are an enchanter, in which case there is a very strong case to turn them into dust and essence for your profession needs. As an advanced tip, you can explore the use of mobile apps that let you post on the auction house at the right time because the price of greens tends to fluctuate rapidly, and could mean a large loss of potential gold income.
The Broken Isles are unique among WoW continents in that you can progress through zones in any order you want. Once you have made it through the initial quests in Legion, you are free to move about four of the new zones — Val’sharah, Azsuna, Stormheim, and Highmountain — as you wish, with enemies, quests, and rewards scaling to your level. The fifth zone, Suramar, is mostly locked away until you’ve reached a certain point in the story.

EXCEPTION: If you have Mining and only use Jewelcrafting to craft stone statues (for additional in-combat healing), then this may be a useful tradeskill. However, like Engineering above, it should not be a leveling focus and should only be used to assist with power leveling. Doing any more than this will become costly and should not be undertaken during the power-leveling process.
From my understanding, the world boss is always there when your faction controls the Warfront. Like other world bosses you can only get gear from him once a week. There are other world bosses in the zones outside the warfront and 1 spawns a week just like Legion. I’m not 100% sure that the warfront will be available on launch but I have yet to read anything that says otherwise. The quest also reset once a week as well. Think of Warfronts like old Tol-Barad
Fishing requires much time and does not yield much profit until its later levels. Unless you enjoy it for its own sake, avoid seriously delving into fishing until your level limit. It is not a bad idea to do a little when starting out a new character on a new server, though - the gray items you fish up sell for good money to a starter, which can help you out with your other tradeskills.
Was doing it at 52 on my lightforged paladin and it was easily the slowest zone out of the ones I'd done. Granted, I didn't have War Mode on so I didn't have any PVP talents, but it felt like about 40% of my time was spent waiting around for respawns or wandering around looking for mobs to kill to get a quest item that had like a 5% drop rate. Maybe I just got unlucky but I definitely won't be going to that zone again for future heritage armor runs.

Many people have asked whether we recommend leveling as Enhancement or Elemental. There’s no definitive answer here; it depends entirely on your comfort, your gear options, and if you’re in a group or solo. Enhancement benefits more from Honor Talents in open world leveling, and Elemental has stronger AOE damage for mass pulling. Feel free to experiment with both specs.
Another problem is that gold isn’t a finite resource; the game is constantly creating more of it. Gold is created every time someone completes a quest, kills an enemy or sells trash to a vendor. Some gold is siphoned back out of the game economy by repair bills, flight paths and a “tax” on auction house sales. Occasionally, a lot of gold is destroyed when someone buys a pricey vanity mount from a vendor. But gold is created quicker than it is destroyed, and it becomes less valuable as it becomes less scarce.

Edit 20 It’s been a week since this post and a lot of people are still reaching out to me with questions which is fine. I have had a few different people reach out to me to help make YouTube videos based off this guide and more info in BFA which I’m more than willing to do. Whoever gets the videos up first I will link them here for you guys to enjoy.