Discounts should be controlled in the Privilege Groups. Administration should have control over which Privilege Groups can apply a discount, same as the Adjust Price privilege.

We only want the owners or certain employees able to do this

We love the structured discounts! But we'd love to have the ability to add a custom price modification or discount (one that's not in the list) a separate privilege. That way, most of our front desk staff would be forced to choose from the preset discounts.