I personally wouldn't recommend Bloodmyst Isle. There's a ton of quests but a lot of those quests have absolutely horrible drop rates on their items. A lot of the quest mobs also have very slow and/or spread out spawns so if there's other people there you're gonna be waiting for respawns or spending a lot of time traveling between spawn areas quite a bit. Overall it's just an incredibly slow zone as far as EXP goes.
If you've been away from WoW for some time, you may not know that the game's Legion expansion focused on powering up an impressive "Artifact Weapon" throughout the duration of the expansion. In short, players have been using the same weapon for about two years now. Artifact weapons were pretty cool and bosses did drop Relics which were used to upgrade them. But after two years of using the same weapon, many players are looking forward to the thrill of having an actual weapon drop off of a raid boss again.
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