Well, that is pretty dramatic. The only niggle for me would be the location of the rollercoaster. It would have been just a little bit better if you were able to move to the right, so that the rollercoaster was not overlapped by the planks in the foreground. Other than that, well shot.
Yes, it is pretty overwhelming, too many interesting subjects which are each for itself. It's hard to say what is the leading motif. Sometimes less is more.
I think timor is onto something, here. If you could shoot with a longer focal lens, and keeping only the rollercoaster and the star trails in the shot, I think it would be stronger. KISS, it's said.