I would have to suggest more guardians (of course) and maybe drop the vyper and wraithlord and invest in a falcon. You don't have much speed in this army, so a falcon would be a great thing to have for flanking attacks or just plain annoyance with a CTM.
Here is my 1k list for comparison:
Seer Council
Farseer: WB, SP, Fortune
Farseer: WB, SP, Mind War
Warlock: WB, SP, Augment
Warlock: WB, SP, Enhance
Warlock: WB, SP, Destructor
16 black guardians, starcannon
Warlock: SP, CCW, Conceal
16 black guardians, starcannon
Warlock: SP, CCW, Conceal
Falcon, HF, SS, Starcannon
2 Dark Reapers
Exarch: EML, Fast Shot
Starts out as a shooting base army, but towards the end the seer council will get in the falcon and clear up any survivors.
I haven't actually used this list yet. The one I usually use has a wraithlord instead of the reapers, and one extra destructor warlock in the seer council. As you can imagine, it is much more offensive than this one is, but I feel like this one would be more fun to play.