If your opponent plays a control-deck, remove the Banishing Knacks with counter, Negate should be enough. Against red/green Flashfreeze is of course even better. Then also try Tidebinder Mage.

Cosi's Trickster and Merfolk Spy can be swapped. Against control Cosi is better, against blue prefer the Spy.

Don't forget to replace the Aquitect's Will with <any card from the sideboard> if your opponent plays blue.