Thank you all very much for your comments - really appreciated.
Donna - Thanks for your question and interest. I always do a study first, in color, on my PC using the Art Rage program. I'm not sure if it influences me in a more digital direction as well or if that's my natural inclination anyway. But it sure helps to try out color schemes. I don't think I could do it successfully 'in my head'!
You could have played it safe and not applied that shock of red paint in the center. It would still have been a beautiful painting. But that blood red application, like a wound, jolts this work into another direction. The sun doesn't simply dip behind the horizon but melts into the very fabric of the city, becoming part of the night scape. I applaud your craft and your courage.