I've done Celtic crosses before in b&w, and it's a bit of a cliche, if you don't mind me saying, Dave. So I thought I'd bring out the "Celtic colours" as some would have it.
Now that is nice. The over-abundance of detail really works here and the separation is created by the colour (I suspect it would look muddled in B&W). I was going to alter anything it would be to trim maybe 10-20% or so off the top to bring the cross into the upper third. Lovely shot - autumn really has inspired you Rob!
Its refreshing to see one in color, Rob, and the colors here most certainly work nice. (Celtic colors...? Its in Edinburgh, no? More like Hibs colors up top, Hearts doon below.)