[ELAY]

I agree that colour, composition, exposure all look good. I do agree with the f/stop comment above -- you have tons of flex, so why not go up to at least f/11 here?

But looking this photo over, and reading your narrative, I have to say that the one thing this photo lacks is a sense of depth.

In trying to figure out why, I had two thoughts. First of all, although the smokestack is further into the frame than the foreground buildings, there are no visual or perspective clues to tell us that. So I don't think having the stack there gets you your depth, at least not the way you have framed it.

Second, I think shooting upwards also flattened the photo a bit, in the sense that you are sort of trading horizontal depth for vertical depth.

I think this works as an architectural shot, but I think you would need to capture some ground or a more clear foreground/middle/background arrangement to get the depth you ask about.

Last note -- I got a Sigma 10-20 for Christmas. Not being a snowshoer I haven't gotten outside with it much. Having said that, I have found that the kit is actually a pretty good wide angle lens at 18mm.