there's no reason to miss any class from D2 in D3 since...Wizard = sorceress, witch doctor = necromancer, barb = barb, demon hunter = amazon, monk = pally/assassin hybrid...ok i guess you can miss druid if you want.
edit: went through and saw a lot of "necro" love. seriously people. LOOK at all the abilities the witch doctor gets. they're almost all just a slightly modified necromancer spell.