This is wonderful! I really like the colour scheme and the distant structures in the background. Conversely though, my focus is being drawn to that lens flair up in the top left. I don't think the city needs it. it feels slightly artificial on your painting. As you progress on this one maybe create a point you'd like the viewer to focus one. A particular building or feature with a bit more detail that brings it to the fore?
Yes, I agree with Emily - lens flares are sometimes a bit naff - they sort of have a 'bolt on' quality, and in terms of Photoshop paintings it can be case of once you've seen one lens flare, you seen them all. I don't think you need it.