WOW just amazing there is very little I can say to make this artwork better!
But one thing that I will say is the sky. I feel like the sky needs a bit more stars and planets to make it feel more like a sci-fi/ futuristic piece of art work - if that was what you were aiming for- .
The horizon is a bit blurred out and I feel like it would be better if it showed buildings for more of an impact on viewers!
Again amazing artwork and I know how much time and effort it takes to make such an amazing piece like this. Good job and hope to see more like it!