As for damage, this to me has never been a huge priority. Do damage when you can but not at the risk of your party. With this in mind, its always safe to use your DoTs. Aero 3 and Aero 2 are great for dealing damage without stopping you from healing. Assize is another great AOE damage ability that should be used off cool down it instant heals and gives mana. Give up your dreams of topping the DPS charts, you are EXTRA damage not THE damage. Another tip is combining presence of mind and thin air for holy spam.