Overall I think it works well. The gun silhouette is a bit cheesy, but not a deal breaker (I don't think it's necessary because you've already got the targeting reticle, but if you love it, keep it).
The blue fade top and bottom is subtle and I don't have a preference one way or the other on it.
I want to say the title text is too small, but I think the graphic of the cityscape and target reticle make the dominant statement here and give a better sense of what the story is about, so the title isn't the main selling point (though it needs to be easily seen).
If I were to revise this in any way, I would try making the graphic image (cityscape and target reticle) much bigger and bleeding off the page, and move the title up a bit to make better use of the space. It might make the visual impact a bit stronger, but I wouldn't know for sure until I saw it.
My opinion: Creating a good cover, ad, poster, logo or whatever is 10% technique, 20% talent, and 70% playing around. Most people quit too soon with "Well, that's good enough!"
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