"You have a great imagination--I love the premise--and you're a good writer, but I'm sad to say that I just wasn't passionate enough about this to ask to see more. I wish I could offer constructive suggestions, but I thought the dialogue was fine, the characters well-crafted, and the plot well-conceived. I think it's the kind of thing that really is subjective (see writer banging head against wall in previous post) which is why some people adore the book at the top of the NY Times bestseller list, and others don't."
My reaction is to end the quest for an agent and go directly to smaller, independent publishers. If an offer comes, an agent can be had. Let's see if a different approach bears fruit.