Wow, that purple sky is just the right balance between going too dark and being unnaturally light. Beautiful colors and reflections, and the bridge makes a great compolsitional element.
IMHO the bridge detracts/distracts from the shot. Also if you may find that sunsets are done a lot here. This means that unless one really pops, it won't do so good. Yours though very nice, doesn't pop unfortunately...
TC