Hi Paul,
At the risk of labouring the point - although I feel it is probably worth it if you want to make progress - is to heed Mal's words about simplicity.
I believe it also applies to the Manchester street scene too, let's try to analyse what we have ...
First I'll list them in a rough order of the amount of image area they take up (largest to smallest);
Grass
Sky
Buildings on left and right
Arndale Centre
Tudor building
Wet pavement
Flower border
Tree trunk
Ferris wheel
Now I'll list them in order of brightest to darkest; (I checked using selection areas for histogram)
Street light on right
Christmas angels on street lamp stands
Lit windows various
White ferris wheel pod frames
Arndale sign
Tudor building surface
Building on right
Wet pavement
Sky
Flower border
Grass
Dome and roofs
Flower bed in grass
Tree trunk
Now let's look at structure, shapes and texture;
Smooth; sky
Rectangular and grid structured; some buildings and their windows, masonry, paving slabs
Angles; gable end roofs, pavement, grass, spokes of ferris wheel, tudor beams,
Curves; ferris wheel, dome, angels, wheels
Random; trees, flowers, grass, stonework
The sheer number of different elements is one thing, but also; they are in such a jumbled order, that nothing of interest jumps out as being 'the subject'.
Yes - you can argue you have a "juxtaposition of shapes" (or ages of buildings), etc., here, but I do think there is just too much.
The most striking images are very often the simplest, so try to look for simpler compositions.
I hope that was helpful to you, I know I certainly found it informative writing it - it will make me think before taking another city scene
Cheers,