And if you've been reading Luke's blog, you probably already know that one of the best argument for theism is the free will defense of the omni-s being consistent with the existence of evil, but since we don't think free will is even a coherent concept, it leaves us unmoved.

Beyond that, it's just not a very good argument. If the entity was omnipotent, it could have given us free will without creating evil. At the least, it could have created less evil by giving all humans force fields, so all we could do to harm each other would be to gossip and insult.