All of the friendly fog and mist spells except cloudkill make it very hard for healers and players to see stat effects like curse.
As a result most groups only carry cloudkill since it provides the 20% miss chance versus raid bosses while not blocking the groups vision.
Many casters would rather carry Incendiary cloud, acid fog, etc... as these do aoe damage as well as provide a 20% miss chance. Sadly these block player vision and hinder groups.
Changing these aoes from the dome with swirling fog to an effect like cloudkill or the pale masters death aura would greatly improve the fog/mist spells. This will allow players and most importantly the healers to see stat effects while in the fogs and still provide the very important 20% concealment vs raid bosses. It would also greatly help players slot a fog spell in the spell level of their choice or of the damage of their choice, providing more versatility and customization.
You can keep enemy fogs as they currently are. Enemy fogs should block our vision, friendly aoes should not though.