Please share advice for my ebook cover?

I just finished making the cover for Moon's Insanity, which will be a free Kindle download. I made it on Paint.net, using a photo I had taken and editing the moon into it, messing with the lighting and adding text. But I could really do with knowing whether or not it's any good. Could any artisans recommend improvements, or is this okay for a free ebook? It's my first attempt at making a cover, so it might just be terrible!

Link ---- http://ljsimpkins.deviantart.com/art/Moon-s-Insanity-Cover-283662441

Oh, here's a thumbnail if it helps any ^^

I like it. It's simple and quite striking, and for an e-book cover, it's effective ^^ I'm assuming it'll be in b&w on the kindle, right?

I don't know, if I saw that book cover...something about it just screams "amateur". \
If it were up to me me, I'd probably make the sky darker and the moon bright, and maybe use a different font (though typography has always been my weak point so I'm not sure what I would replace it with, just that it could use replacing.)

A couple of quick examples of what I mean (just tweaked the brightness/contrast of the background, one layer darker and one brighter for the moon; I didn't do anything with the words)

I'd move the words away from the edges and corners. And geez not a fan of that font, mainly that ' (I can't spell today).

I'd recommend going on dafont.com, there's a lot of free fonts on there which are nicer than what you've got.