Hah! You had the same idea as me, except I went to Salisbury! Thought about Winchester though, perhaps another time, another challenge...
One idea, assuming you shot this in RAW might have been to add a little more shadow in to give contrast and depth to what is definitely a very deep subject. Just a thought...
Do drop me a PM if you are shooting in Winchester again!
Just saw a similar picture without the stained glass ... it was squared up better than this one (though this isn't too bad). Would have liked to see more color from the stained glass, it's kind of uninteresting here.