Good picture. I love how, despite the rain, Robin's out there protecting the city (an it looks like he has been out for a while judging by his hair).
The only thing I might change (since you seem not to like the colors) would be to make the clouds darker in the sky. The way they are now makes them look like the sky is clearing up when I can clearly see the rain coming down heavily. In addition, make Robin's red shirt darker. In darkness, red actually will look black because those light waves are some of the weakest and the first to be lost to our eyes.