The only thing i could really ask for in this expansion is new combat sounds.
Nothing bothers me more then when slicing/smashing/impaling monsters is the sounds of the blade/hammer/axe hitting them. Currently the sounds are extremely low, the slicing sounds like whiffing, and the hammer sounds like soft knocks. Its very hard to determine whether you hit an enemy or not because the sounds are not distinct.
Combat sounds are extremely important in both Immersion and Gameplay. Having a good impactful sound makes it easy for a person to understand whats going on in the battle. As for immersion, the combat sounds make the battle feel like a nerf war with your brother or sister.
Please Anet, if you can offer us new combat sounds i would spend extra money in the Black Lion shop!!