Not sure about "breaking the rules," as it appears to me classically composed. There is a diagonal leading line from bottom left to the intersection of thirds on the upper right. The main point of focus appears to be the darker tree that happens to be in that intersection of thirds. All that is fine, nothing wrong with the composition, classical or not.
That type of image, with a lot of intricate detail, works best when printed really large, so that the viewer can appreciate and examine it slowly, in several steps, rather than absorbing the whole image in one go. The smaller the image, the less detail and more simplification is needed (think Michael Kenna, who rarely prints bigger than 8"x8"). On the other end of the spectrum would be, for instance, A. Gursky with his "99 Cents Store."
Back to your image, I might vignette the bottom a bit, to balance it against the dark sky.