What should an NFL safety be able to do?
Zone coverage ability is the most important thing, closely followed by a players’ usefulness in run support. Even in zone coverage, some players are better deep (the deep center fielder is a particularly rare breed), while some are much better closer to the line of scrimmage. The smartest coaches utilize their players’ strengths accordingly. Even run support requires slightly different skillsets depending on where a player lines up.
Man coverage ability, especially against tight ends and running backs, is also desirable given those positions’ increasing effectiveness in the passing game, while the ability to blitz is a nice bonus.