We don't know yet. They said when asked that they intend to implement all of the main classes from PHB, but gave a specific measured response that the races revealed so far are all they're talking about for now. There will be more, but at this point it is pure speculation on anyone's part which other ones will be yet added.

“Any fool can criticize, condemn and complain - and most fools do. But it takes character and self control to be understanding and forgiving.”---Dale Carnegie.