Thanks to all for the comments. I suspected that the selective colorization might end up being the focus of concern, as I myself often dismiss such things as gimmicks with no real purpose other than to be "different", and usually just detract from the monochrome form. In this case it has a real purpose, one possibly too obscure to be apparent to anyone but me. I considered partially desaturating the leaf to decrease its prominence, but maybe it's just a bridge too far. So I'm adding a less provoking version, with distraction removed, for examination.
