The biggest backdrop of Battle for Azeroth is the budding of a war between the Horde and the Alliance, two opposing factions that have more or less been on the same side of various struggles for a number of years. The separation of the two factions was refreshing and reminded me of leveling through vanilla WoW with unique zones given to each side (at least at the beginning).
Fifth: As for Azerite Armor, I recommend getting the Chest first from Magini and if you do Vol'dun first, the first piece you can get will be a Head and the final piece from the zone with be Shoulders. That will give you all 3 pieces of Azerite Armor when you leave the first zone which will help out. If you are leveling a different spec from what you plan on playing, (i.e leveling as a dps when you plan to heal/tank) you will receive at least 2 pieces from every zone then 1 piece from starting the War Campaign that you can choose your Main Spec trait for. Pick the traits that will help you level the fastest.
Once again, as soon as you hit 70 - I recommend to go and learn faster flying. This speeds up your questing A LOT, and is worth the time and gold. It will cost 4500 if you go to the capitol, or 5000 if you prefer Shattrath/Dalaran, because you will not have reputation with them at that point. This price will sadly be above what a totally new character can afford, if you don't have any Main. But you should go and buy flying as soon as you have enough money.
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