Let’s do something fun!
We’ll make a tier list over all the classes in the game, from S-tier to F-tier. You will have different reasons to place classes in other tiers than me, but please do elaborate why you place a class in the specific tier 
I have been playing this game for nearly 15 years, meaning I have had experience with all classes. Some bias will probably occur, but I’m trying not to be.
Note that these are my rankings, so don’t attack me if you dont agree. Keep it polite
S-Tier
- Druid.
Love their overall variety, utility and lore
- Warlock
Their master-of-demons aspect is awesome. The most unique caster spec and the fact that they are a bit tanky, is cool.
A-Tier
Mage
To me, probably the class with the most different specs in term of gameplay. All three of the specs are vastly different to me, which deserves a high ranking imo.
Shaman
Lots of cool stuff going on with shaman. Summoning elementals is awesome and the lore is really cool. Not my favorite class, by quite a bit, but deserving of a spot in the A-tier.
B-Tier
Rogue
Love the class. The three specs are different enough to add variety. Not too much interesting stuff going on, tho.
Priest
I have always liked holy, but I LOVE shadowpriest. Probably the coolest spec in the entire game for me (too bad its in such a bad place). Disc however, Ive never liked. Its unique and adds variety, which is a plus, but its just not for me. Priest would have been A-Tier for me without disc.
C-Tier
Hunter
Cool class, just a bit boring. Nothing special going on with hunters imo.
Monk
Never been a big fan of monks. They are all right and all, but its not my style. Without the variety of specs, monks would have been a D-tier class.
Warrior
Nothing special or unique going on. I main a warrior, but its still a middle of the pack class.
Paladin
I like the lore, but I’ve never enjoyed playing a paladin. Cool class, tho.
D-Tier
Death Knight
Never been a a huge fan of DKs. Their lore might be the best in the entire game, but the gameplay just doesnt do it for me.
F-Tier
Demon Hunter
They are currently too strong compared to their ease of play