Yeh, I gotta say when you have a perfect balance of the three primary colours, what is the point in going mono? I love the colours as they are. Yes, I agree the angle taken coule be a bit more imaginative but having said that it does give the picture a sense of balance and I rather like the fact we can see the whole building and the sea either side of it. Not quite sure why there seems to be some lines just above and parallel to the roof top.
With regards the mono though, I had a go at converting to mono using my favourite Lab Mode method and this gave a lot more contrast to the picture. Maybe too much but I only did it to see what we could get in there. I did not use any curves for this at all, just used 2 extra layers blended with Overlay mode, the first at 100% opacity and the second at 35% opacity.
Just a different option to compare. See what you think.
Cheers,
Rob