Prepare the Horde for war by recruiting the ancient empire of Zandalar. In this troll-dominated territory, ancient evil waits to be unleashed on the world as you battle crazed blood-troll worshippers, gargantuan dinosaurs, and titan constructs. Discover Zuldazar, the oldest city in Azeroth; unveil the bleak swamps of Nazmir; and traverse the deadly deserts of Vol'dun.
Drustvar is far and away the hardest Alliance zone, which is exactly why you want to do it first. If you have legendary items, they’ll still be usable, and if you don’t, this zone will still be easier early on than it will be later. Drustvar is also extremely fast and will let you jump out ahead of your competition in other zones, which means fewer players around to take your quest objectives.
If you love running old content for transmog items, you'll love the new legacy loot system. Whenever a player enters a dungeon or raid where they are 10 or more levels above the content, the dungeon or raid bosses drop an amount of loot equivalent to what would have dropped for a full group when the content was current. That means players could earn loot for five people in dungeons and loot for 20 people after soloing a raid. The legacy loot system also drops other gear types, like cloth dropping for a plate wearer. It's now much easier to get the transmog gear you want, and you can also collect gear for your alts on the same run.
Despite all of these problems and this laundry list of glaring systematic issues, the crowning achievement of Battle for Azeroth’s endgame is that it still remains enjoyable all due to those two pillars of raiding and dungeons. That won’t last forever. As the expansion goes on, and the grind necessary to progress becomes even more demanding and the time spent in content that simply isn’t fun increases, it will be harder and harder for raiding and Mythic+ to carry the expansion along.
At the end of Legion, the titan Sargeras was imprisoned, but not before he plunged his sword into the planet Azeroth. This not only devastated a massive area (much of the desert zone of Silithus is now cracked and scorched), but badly wounded the gestating titan inside. While the heroes managed to ablate the worst of the damage (at the cost of the majority of their artifact weapons' mythic power), the world is still wounded and bleeding a substance called "Azerite," which has great magical potential. The Horde Warchief, Sylvanas Windrunner, attempts to consolidate Horde power on Kalimdor and gain a monopoly on Azerite (which is primarily found at the southern end of the continent). Her campaign to do so, the War of Thorns, formed a pre-launch event for the expansion and ends with the major Night Elf holdings on the continent seized or (in the case of their capital city of Darnassus) annihilated. The Alliance makes a retaliatory strike against her home base, the Undercity, which was formerly the human capital of Lordaeron. This succeeds in driving the Horde out, but before leaving Sylvanas saturates the area with disease and toxins that render it uninhabitable. With this tit-for-tat military exchange, the Horde has almost complete control over Kalimdor, while the Alliance has near-total dominion over the Eastern Kingdoms. With further conflict inevitable, Battle for Azeroth takes the two factions to the continents of Kul Tiras and Zandalar to recruit new allies in order to turn the tides of war.
Players who were around during Mists of Pandaria might recall a dungeon mode called Scenarios, which involved teams of three players instead of the traditional five. Island Expeditions bring a similar feel, with groups being tasked with plundering treasure off various islands. Your team faces off against other players or AI-controlled characters from the opposing faction and whoever can collect the most treasure, or "Azerite," wins.
As you're leveling, I generally recommend you just follow the natural flow of the progression through each zone. They're laid out fairly reasonably. But don't be afraid to hop around, especially if you're near a quest objective. You shouldn't actually need ALL of the zones listed to reach 62. Pick the ones you like best. It's much more important to simply be as focused as possible and flow from one quest to the next.
Unfortunately, the BfA prepatch took away more than usual--having an entire expansion balanced around an ultra-powerful weapon that abruptly turned into a dead stat stick made the end of Legion particularly depressing--and offered very little in return. The patch didn't flop because of bugs; it failed because it's boring, unrewarding, limited, unambitious, and actively feels like it's punishing players at a time they should be celebrating.
As for the classes themselves, they almost all play like slower and slightly less interesting versions of their Legion counterparts. This is thanks in large part to the loss of one ability from each class that came along with Legion’s own AP dumping system: the artifact weapon, which added a unique ability to every spec in the game. The loss of these abilities left most classes feeling frustrating and incomplete, and though Azerite gear was supposed to be the replacement, it missed the mark completely. There will always be one Azerite trait that reigns supreme for each spec, meaning that the frustration of that particular loop will be unavoidable as long as the system is in the game.
This expansion suffers from the Warlords of Draenor (WoD) effect, initially, players will think this is a great expansion but upon investing some time into the game they'll realize this game is a disaster. The pre-patch should have been our first warning with how poorly designed and executed that fiasco was, but beyond that, let's look at what the expansion itself offers:
For Alliance it's Lok'Modan, Redridge, Darkshore, Felwood, Stranglethorn (both parts), Plaguelands. Somewhere between 3 - 3.5 of these get you to 60 in like a 16 hours /played, if you queue for dungeons at the same time. I recommend dropping everything at 45 and going to Darkshore-Felwood if you didn't do them yet - they are literally the fastest levelling zones in the game right now, maybe only trumped by Silverpine.
Dugi’s leveling guide is the leveling addon I’ve always used to level as fast as possible. It will show you where to go and what to do in-game, speeding up the leveling process. This is optional though, as the game already does a pretty good job at showing you where to go at all times. The addon does, however, come with a couple of other nice features and perks.