Yes and no. Your mage would have the melee +X and piercing +X traits until the end of the round, but Battle Fury does not benefit from melee +X since the errata. You only get to use melee +X on the first attack of an action for which it is relevant, and Battle Fury now counts as part of the same action. You get the piercing for all of the attacks though. In addition, you could make use of the melee +X again if you were attacked and you used Retaliate to counterstrike.