Although I doubt that Blizzard will make it. I think a Demon Hunter would be a great class for Diablo. Diablo is a demon, so I think it's necessary to have a demon hunter class. I think a good example is the whip wielding vampire hunters from Castlevania. I think whips would be a great and fun weapon to use. The animation would look pretty cool too. The class would look great as a male or female (female with tight leather and whip... mmm....). It also can be considered as a ranged weapon too or more of a longer distance weapon.
http://www.kbgames.com.br/kblog/wp-content/uploads/2009/07/castlevania_symphony_of_the_night_06.jpg
What do you think?