As a WHM main regen is all youll need for everything except the tank, only need to throw a cure or cure 2 when dps/healer is in critical health. Its one way to stay mp efficient by reducing overhealing plus even healers should play their part in dps to make run go a little smoother, cant do that if your just healing 100% of the time. I set my RegenCureHpPercentage at 40% and its working awesome.