Flight,
The A321 was also designed with relaxed stability in pitch ,or so I have been told!The reason was so that the area of the horizontal stabiliser could be reduced along with the downward forces on it. Obviously this produces less empennage drag. If you look at a plan view of a 321 compared to a 757 it is noticeable.
With the F16 the aircraft was designed to be unstable in pitch to make it more manoeuverable(as said CP in front of CG).Fly by wire was used to allow a mere human to control it!
The A320 has CG in front of CP, but they are nearer (static margin I think ?) to each other than is usual so slightly less stable.
Funnily enough the Panavia Tornado was built so it was stable. Massive tailerons and fly by wire were used to increase it's manoeuverability--opposite way round to F16. Different design concept I suppose?