i only played for the first two months of the expansion, might resub for an additional month and check out all the things they added since then.
i really enjoyed shadowlands in those first two months, pretty much everthing was very interesting and beautiful, i liked how my four chosen classes for the different covenants felt "at home" in those regions (hunter/ardenweald, DH/revendreth, paladin/bastion, DK/maldraxxus)
i also want to praise that they finally dedicated "an entire zone" to slimes!
alot of slime pets and quests and maldraxxus in parts was just some kind of slime playground ^^
im a bit of a slime fan so that was really cool for me :>
other than that, i also enjoyed the different stories in each zone, the general theme of revendreth was especially awesome!