Shammies have the most controlled burst.

Ferals or Rogues would have a devastating opener.
And then frequently re-stealth.

The 4x Frost, 1x Healer looks promising.
Howling Blast vs AoE/masses attacking and Necrotic Strikes for anti-healer attacks.

For the sheer pissing off, people despise:
- Stuns... Rogues.
- Dots... Warlocks.