Thanks all for the helpful and considered opinions, exactly what I was looking for
Let me respond to a couple of the points: the two shadows at bottom right, I agree Iain I wondered for a while about those and whether to attempt to clone them out but I left them for two reasons> The first was I was determined to put a shot up that I hadn't cloned in any way at all so that all the focus would be on the picture as is and not the rather tedious 'is it as was or isn't it?' stuff that opften takes over threads on these two display boards. The other is that I didn't feel removing them would be very convincing as there is not enough space let to clone from without lots of repeating patterns or ages doing it to source from different places constantly. Looking at them (they are from trees behind me, not my legs though some might argue my legs are like treetrunks anyway!) they are angled towards the main subject so I felt they were appropriate lead-in lines so were on balance probably best left. If anyone wants to try and remove them convincingly I am more than happy to let them try.
Is it over-saturated? Actually No I don't think so, it is as close as possible to how I saw it. The time was about 7.15am, the sun was just up on a very clear morning and the golden light was as strong as I have seen it for a long time. I might have lifted the reflection very slightly higher than it was but it really was VERY clear and colourful because the sun was striking the walls directly.
The edges of the building have not been touched in any way at all, the sky is the original. I think what makes it look a bit strange is that it is (of course) a ruin and the dark strip along the top gable is simply the shadowy brick surface which is usually absolutely covered in seagulls and pigeons! I can however see a slight line between the left of the roof and the sky but I must put that down to the compression as it isn't evident on the original at all.
I did increase the contrast as RAW pictures usually need as they are generally a bit flat. I considered using the famous LucisArt filter on it but thought better of it to keep it as was. The one area of building to sky that I would like to get a greater contrast is the chimney type structure where the right of it almost blends into the sky. I could go in close, select the chimney and burn the edge in slightly I guess.
If anyone would like to try and convert the colour to mono again, feel free. There are a hundred different results you can gain from playing around with the channel mixer but I chose this one because I wanted fairly high contrast and a full dynamic range. I also wanted to keep as much detail in the bluer part of the sky as possible.... but I wanted the conversion to be all one layer, not selecting different parts and converting them separately. That was in order to maintain the balance of the scene.
I think I agree with Fiona that a more textured sky might work better for a mono to give it mnore atmosphere. Might give that a go at some point. As I said, this time round I went for as close to as was as possible.
Cheers, the comments are really helpful and it's great to see a variety of responses.
Cheers,
Rob