Rogue is my ideal class thematically, but I just don’t care for subtlety in its post-legion form.
So, warlock! Warlock is never bad. Even when it is, it’s brief and you are wanted for portals. Our scaling usually gets nutty, and chaos bolt destroys people.
Thematically, we are the only truly evil class. Yes, even more than DKs. Our class quests in vanilla>wrath were the best by far.