Getting mutas/lurkers using 2hatch faster on Tornado makes all the difference. Every game I've gone 2hatch I've won by only a slim margin; 3hatch games are incredibly frustrating and I lose a lot.
Sparks Terran builds give me the biggest trouble here too. I know the build is designed to carve up my sunkens, but either players I've gone against recently are much faster, I'm slower, or Tornado seems to really favor this build.