This won't be a rate, maybe I'll edit the comment, but why not just change Skarmory for Landorus-T ?
You got a wall of the same caliber, as well as a way to kill Volcarona. I'm pretty sure a Rock Polish set (not a double dance) with SR would be a perfect fit to break wall or sweep late game.
You could also go for the full defensive set. I'll think about it to give you a better raten this was just food for thoughts.
PS : If you're afraid of not having a steel wall against Dragon, keep in mind that you already have the fastest one in OU, and I don't like fixing rules like "get a Steel etc". If it bothers you, you can still put Scizor over Lucario.