Heart of Stone with NG+ is pretty .. easy ?

I'm level 68 ( DeathMarch + NG plus ) right now, after completed main story I decided to play Hearth of stone DLC but I found it not so hard, the boss fight with the Mage at the start of the DLC is pretty damn easy to me, is that normal ? or because my gears is too OP ( master crafted with 20 % bleeding effect ) ? Will it be any harder ? I'm considering to play the standalone version of Heart of Stone, should I do it ?