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You could switch out the lead metagross with Hippowdon. That way you can set up sandstorm and rocks early plus you get another defensive beast. I'm not really sure if you want to keep the ScarfTar since Ape and Starf Scarmie are everywhere.
It seems to work pretty well actually. The only nitpick I have with it is that you have 3 pokemon weak to EQ. But the team is really well built, really resilient too.