Since it's like a premium version and it's not modifying game files it gets by somehow. I personally hate Zygor's guides and always have, it's just personal honestly. I understand some people like his guides and have no problem paying for them but I personally hate the idea of charging someone for an addon that - as this post points out - has plenty of bugs in it. These were fixed last week and if I'm paying cash for an addon I want that addon bug free and not causing a hassle and taking my time away when I could be doing a better job without an addon at all.
Compare that to the previous Warlords of Draenor expansion, which wasn't a great expansion overall, but still managed a prepatch that offered a pet, a title, a new version of an old dungeon with new quests and achievements and loot, a series of ultrapowerful weapons that could be passed on to alts, and a whole host of in-game system improvements ranging from a new way to find groups to a new way to collect pets, toys and appearances.
Anyway both got to 110 at around 50h played. I messed up with my Pal by going to Legion once I hit 100 instead of finishing treasures and bonuses in WoD. All in all, if I picked the best zones and was only trying to level as fast as I could, I would probably could have done it in roughly 40h. Note that it would have a been A LOT faster with a Monk as both Ret and Rogues don't really have a decent AoE until 40+ (45 for Ret and 63 for Rogue I believe). The daily also helps a lot. I know that leveling my Monk before the pre-patch was insanely fast. Might be slower with the changes to FoF, however.
I do not recommend going for TBC, although I remember Hellfire peninsula to be decent, everything else is rather slow. Instead go for WotLK, Borean Thundra gets you levelled very fast, and then you can head straight for Icecrown at 67, which is also insanely fast, although admittedly has a few elite quests. You can go to Sholazar Basin alternatively. 2 zones should get you 60-80 no problem.
EXPLORE TWO FABLED KINGDOMS – As a champion of the Horde, travel to Zandalar to persuade the trolls to lend their naval might to the war effort. As a defender of the Alliance, sail to the seafaring kingdom of Kul Tiras, home of Jaina Proudmoore, and rally its inhabitants to fight for your cause. Once you’ve successfully recruited one of these proud kingdoms to your faction, infiltrate the enemy’s newly claimed territory.
Meanwhile, on the island continents introduced in the Battle for Azeroth expansion, players level 110 and above who have unlocked world quests can participate in Faction Assaults. These special events, alternating between Alliance and Horde territory, will give each faction a chance to band together to defend their territory or invade their enemy’s via a series of world quests. The prize? Survival! Also faction, gear and gold. Maybe even some pride.
War Mode, which allows players on PvE realms to turn on PvP combat and PvP realm players to turn it off, launched--offering a fairly measly 10% extra experience to leveling players for the privilege of getting ganked by max-level characters, or 10% increased world quest rewards for level-capped characters. For many players, that's not much an enticement.
I liked the little discount for the weekend special. I was used to buying other expansions that included a 30 game time card, this did not. However I was prompted to spend gold I had build up and saved, previously playing the game, and it cost me 117000 gold deducted from my combined characters on my old main server. Big download, so I had to wait to play it until the next morning. Gameplay is different, I was used to the old talent point system, alas I had 10 lvl 100 characters, max level garrisons and shipyard. I did the only thing thinkable without having to take time to vendor unusable items that I thought had meaning. Created the new class. Tutorial started at 98, to get you to 100 with a slow intro back into the game. Auction house prices are pretty high with how long this game has been around. I hope to play more soon, but not like the hardcore grind years past. All I know is I am spending remaining gold saved on biggest affordable bags, and whatever flight trainings to keep me moving fast. Game looks good, no lag, I already enjoy the storyline again.
Some people have made arguments that quest blues can sometimes be more powerful than heirlooms, especially with sockets. I'm not convinced. The simple fact that you never have to even look at quest rewards will save a non-insignificant amount of time over the course of leveling. Also of consideration is the value of enchanted gear never having to be re-enchanted.
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.