[fghvbnvbnfe]

As as been mentioned, integer bounds for one. Using aspects in Ada will also let you provide other assurances (at compile time or runtime, depending).

Additionally, the "newtype" in Ada is far easier to work with. The new type inherits the operations of the parent type. When it comes to this sort of thing, it needs to be as simple and easy as possible or it just doesn't get done consistently.