Here are my ideas for the classes that should be present in the game (including future expansion packs) other that the ones that are already confirmed:
paladin/crusader (they’re basically the same), demon hunter (but without the “machine gun-bow”, automatic sentry guns, and other such ridiculous abilities) , monk, amazon, a pure archer/“nature” archer (like a ranger), necromancer, your death knight idea, assassin (focused on melee, to distinguish it from the demon hunter), a cleric/priest (mage+holy warrior) (though arguably, it would be too similar to the paladin/crusader), an archer+mage class (shooting magically imbued arrows and projectiles) ( though arguably, it’s too similar to other classes on this list) , and a heavily armed and armored “sword mage” (mage+sword and board)
I would also like to see another kind of melee mage, maybe a mage that transforms into lightning or something like an archon from Diablo 3, and then attacks rapidly in melee ( a sort of agile melee glass cannon); but I can’t think of a way to make it distinct enough from the assassin and monk.
finally, I liked the “wise old man” (especially his life experience, like when he talked about when his sister died) aspect of the witch doctor from diablo 3, but I don’t know what gameplay style to pair with such a character, maybe something like a more tame druid? (without melee and shapeshifting abilities) like a shaman or something?
on a side note: please don’t include any technology that’s too advanced for classic medieval fantasy (like the sentry guns from the D3 demon hunter, or the whole steam technology in the warcraft/world of warcraft franchise). in my opinion it ruins the “feel” of the game.
Maybe they can include some basic gunpowder weapons and grenades but that’s it.