I like the discontinuity between the top and bottom halves.
I agree. having them completely seperately works really well. but I'd have accentuated it a bit more:
Maybe try rotating the shot slightly so that the bridge is perfectly parallel with the top and bottom of the picture (this is where I would have said take the shot again, as in rotating it, you will make the waves of the water no longer parallel - but hey! thats just me).
Also, try cropping the shots so the the bridge is dead in the centre between the top and bottom. These seem like small details - but those are the ones that will make shots stand out against others.