Today 2K Sports has released a major roster update for NBA 2K15. It includes changes to every player in the league which will make the gameplay more realistic. The update decreased every player's standing and moving 3pt and mid-range shot ratings by 8 points.
These attributes were globally adjusted based on shooting percentages from the latest patch. According to 2K, due to these new changes, some player's overall ratings may be drastically different than before. These changes are now included in the latest roster update (April 3, 2015): http://www.nba2k.org/2015/04/nba-2k15-roster-update-changes-april-3rd-2015