I have not seen anyone mention this so i will go ahead and see if anyone found this a problem. When you toggle off the sub target command its impossible to heal anyone including your self when targeting a monster.
I would like to request just to make abilities that only effect hostile effect the sub target command.
Example: Playing as PLD, if i try to use Holly Succor it will say you can perform that action on the target.
This is not much problem on whm cause I hardly ever need to target the monster but it does suck solo when you need healing, and have to keep deselecting the mob to heal your self.