Colors are a little faded...maybe some increased saturation might've helped? I think this would've looked really cool if you had dropped a pebble in the water near you to get some rings and then rotated the picture 180 degrees....would've looked like rings in the sky then.
Clever idea. If possible, I think I would have tried shooting this (or rotate/crop) so that the roofline was either much closer to being parallel to the image boundaries, or much further off. Even though it's a great reflection, the color of the water kind of muddies (no pun intended) the colors in the reflection. Maybe if you tried adjusting the levels a little bit to make them a little stronger? Finally, it looks like everything in the shot is reflection except that little bit up in the UR corner. I think I woud have tried to crop that out and made it completely a reflection.
The colours here are so murky, it doesn't really make the reflection pleasing to look at for me. The building itself is a good subject, just a shame the light wasn't a bit sharper on the day, or something.