There is a limited amount of development resources. So what feature is MOST important to you? Would you really want to see dueling put into the game at the expense of other features?

Who says that crafting isn't already expansive? This poll is bad because you don't really know if they went to implement dueling would affect crafting.

Who on earth would pick duelling over crafting?

Hmm...making something that helps earn you in game currency more deeper and meaningful or something that allows you to whack at others. That's not a hard choice.