Help with Magic the Gathering deck?

I would put in the Haunting Echoes, Traumatize combo in. It seems like you are also going to try graveyard control, so this would help too. If anything, Traumatize would help you get more targets for Geth. Maybe go for Avatar of Woe. She'll definately clear the path for you. I'd even throw in Levitation, just so that your nonislandwalk/nonflying creatures can attack once Stormtide Leviathon hits the board.