Waiting for the Walk of Witness

I bought a kindle book on black and white photography which is making my head hurt... And that is my excuse why all the photographs of the Walk of Witness that were in my head turned out as rubbish; or at least that's my excuse.
For a few months now I've shot my mono photographs in colour but then simply flicked the saturation to the left in PS and there's a mono pic.
Today I started to photograph in RAW, then I fiddled with the colour in Camera RAW and then flicked the saturation elder to the left in PS.
It does look better than the version that I did nothing to except desaturate but I wonder what I could have done better... Any comments welcome!
ps I've already bought the paracetamol that Mr Hobbs suggested...

I've already decided the whole thing was too light and replaced it with a darker edit. The version I originally posted is here.