This is an interesting case to me of, it almost worked. The scene is good, but the donkey/mule is not quite right. I like that he balances with the tree on the left, but I think you wished you could have printed it all a bit darker but the donkey would have been even more of an issue. I think this is one of those cases that "damn, so close". If he was more distinguishable, or turned a but more, but this is just a case that it didn't all come together as much as we would have liked.
I pretty much agree with Michael. Every element in a successful photograph should be just so. The bitchin part of photography, like the bitchin part of fishing, is having the patience to wait for "just when" or nothing. As you've made long exposure star trail images, you've obviously got what it takes to wait until it all works.