Isn't the whole point of this deck to make you opponent unable to attack you? Maybe some SoDs or Lightnings would work if you need more stall.
At most, you can stop 6 creatures from attacking. Also, this deck relies on a 3 card combo, so it's harder to pull off. Reminds me a bit of liquid antimatter though.
Given he can stop 6 creatures with SoW and 6 with Lightning this makes 12 creatures. Against 30 card decks I rarely see more
than 8 to 9 Monsters so it might work.
But personally, I'd like to have some critters on my own. So maybe I'd try a Spider Fractal deck, or as already mentioned with TU. The shields powered by Mark.
Though that would be a very different deck