They mostly took the words out of my keyboard; very balanced, love the smoke, but also like the colour as it is, and would only crop an inch off the sky.
Yes, everything is squared off and nicely balanced. I remember sights such as this when I was on a barge trip in The Netherlands a while back. Nice colors for an overcast day. I would suggest that some of the sky be cropped out as (forgive me) there is little of interest there and much action on the water.
Lots of interesting elements in this - the Nelly, the smoke stack, the yellow stripes on the building across the river. Maybe with a little work, that sky could look fabulous!