Berzerker Barbarian
Oathbreaker Paladin/Paladin of Vengence
Hexblade for Warlock
Champion for Fighter

I would say id like to see bard but unless they add the colledge of swords I highly doubt I would ever consider main playing a bard.

Sorcerer - Is the lowest on the list I am looking forward too and from looks of it lower on the list to be added. Sadly I expect it will be a while before we see monk as well.

I feel most probable next class to see added will be paladin barbarian or bard. With barbarian probably being the most likely which is a cheer as much as paladin or barbarian would both make me happy personally.