A waiver system is a nice idea but it don't change the main point here.
Good players that are released during the season go below the radar of standard check by most of the teams.
The problem is to differentiate players released because of cap considerations to those released because of their poor values and potentials; as of today you have to check each individual cut to differentiate one to the other or make a general check in the free agents "just in case".
Maybe a notification that a player with at least 50 (maybe higher) current rating or 60 future rating got released will make those good player cut during the season more noticeable.