I do miss dual / multi class but I can live without it if the game is good.
However, I do wish to see more of different type of dual class without limitations per se. Rather, it's an intergration of classes.
Exampes:
Fighter / Mage. Pure melee fighter but can enchant weapons with elemental damage to adjust his or her damage type against certain enemies that has protection. This rather than relying on specific gear you need to hunt for and swap around constantly.
Cleric / Hunter. Arrows that fires can explode on impact healing friendly (not just party members) in certain radius range.
Paladin: No dual classes. The one class that's always been sacred to me and would never change.