I am not familiar sith all the classes available in DnD, and so far I was most anxious to see the assassin arrive ; however some kind of demon focused warlock sublass that could summon big bad ass demons (something more impressive than an imp or some other little critter demon) or even transform into one would be a big wet nerd dream, however i'm not sure if these exist in DnD. Also any class that can have multiple summons, I would be super hyped (again not sure those exist, just saying what i would love to see).
