Nice shot. IMHO I would have added more sky or more H2O and not centered the monument. Spent many years in DC and I used to love to do downtown at night and shoot.
Thank you, believe it or not this is the cropped version I took out sky so as not to have monument in center If you look you will see it is in upper third of picture. If I crop any more it will lose the look and feel of vignette.