It feels more like "black bush" - with the sunset as coming as an afterthought. I'm struggling with your composition here. I appreciate your planning, wanting to frame the distant sunset, but the "frame", big as it now is, seems to be overwhelming. Well, to ME it does...
I was actually shooting something else, and saw this. I only had a couple of seconds before I lost the sun completely, in fact I only got about 3-4 shots of it. I wasn't sure how I was going to like this, or if it would work well.
I like it, but I see your point. There would have been better ways to frame/shoot this.
Too much frame and not enough centre of interest is another way of putting it. Sometimes a photographer needs to realize that a nice scene does not always translate into a nice shot. In this case, even with a 500mm lens, there would still be the haze problem in the distance and the depth of field problem for your frame.