Personally I'd give Forretress Explosion over Spikes or Toxic Spikes just to give it more offensive capabilities in a pinch. Maybe getting rid of Toxic Spikes would be your best bet since you already have Toxic on Shuckle.
I'm curious to see why you'd allocate your Mega Evolution space to Lopunny rather than Gengar. Mega-Gengar's ability to trap opponents is huge (at least in the Gen VI meta) - Mega-Lopunny is a good Pokemon but I don't think it compares to Gengar. It would do decently with a Life Orb, too, so it's not like the switch is crippling.
Other than that I like your team!