Expert Belt could be nice to make sure Dragonite will fall to Stone Edge.. And you're right. I purposely used Leftovers so it could cancel the hail damage, and because I think Virizion is just too bulky to use a Life Orb on it.
As for Foul Play, Smilodon said it. It's very nice as a surprise attack to in-coming Pokemon and actually deals a respectful amount of damage.. I tested out Night Shade before using Foul Play, and I found Foul Play to be more useful and does more damage most of the time.