You likely won't want to drop Powerful Aura since that's how heal tempest maintains fury in its subgroup. You can recover some of your lost healing outside water though with Signet of Water and Wash the Pain away. You would also likely not want to take staff unless your group really needs giga healing. With Sc/Wh or dg/Wh you will be able to provide 25 might, perma regen, perma fury, perma alacrity, perma fury, perma vigor and rebound allows for some special strats on some raid bosses.