This kind of storytelling comes with problems, ones that players have been facing since the early days of the silent video game protagonist. Players in World of Warcraft have so much agency and choice when it comes to their own characters and how they build them. But despite their importance to the world itself, they can do nothing to change its story.
The vanilla WoW Horde leveling guide you see on this site was originally made back in 2006 by Joana (AKA Mancow, or FuriousPaul). The guides have been tweaked many times over the years to make things "faster". The leveling guides were made because of all the messages I got from people asking me how I was able to level up so quickly on new realms. I was first to level 60 on 7 different realms (3 with Mancow and 4 with Joana), even winning Blizzard's "First to Level 50" contest they held back in 2006.
Heirlooms: Heirlooms are the best source of bonus XP for leveling. All slots can be gotten pretty easily now, except the rings. The time you need to spend to get the rings if you haven’t gotten a level 3 shipyard in WoW is way too long, so getting the rings is generally not worth it. Having all your heirloom gear will boost XP by 55%. Generally, you want heirloom gear with crit on for leveling as you want to kill mobs in a few hits as possible
Get your item level as high as possible. Having the best gear is always going to help you when clearing content, so upgrading your individual pieces of armor will be important in the first few days after the expansion’s release. If you’re looking to get ready for Uldir, then you’ll want to be around item level 350 by the time that raid is released on Sept. 4.
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.
For reference, my previous best time abusing Method-0 in 7.3.5 was 32.4 hours(as show in the old thread). A difference of just over 8 hours; which isn't all that bad, all things considered. And I believe I made several errors along the way, which could be cleaned up in future runs. I believe that that gap could be significantly closed by using a monk's bonus, but I hate playing monk...so...yeah. YMMV