
EDIT: Figured I'd show what I'm talking about with a quick edit ^^
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The biggest issue is the highlights of your trees reflecting a yellow sun in a moonlit scene. The highlights on the bench and rightmost bush too. The tree in the distance on the right side looks great. You'll have to tone down the yellow on the clocktower / Big Ben thingy when you shift the hue of your foreground trees toward blue (or at least a little more towards purple).
Other than mostly a few hueshifts, you've got it well enough to work value-wise. Looks cool.
The only thing I'd consider changing a bit value-wise is the deep blue in your shadows -- brightening it up a little so that it can be perceived a bit more easily. In such a dark scene with such a bright moon, you should at least get to see a glimmer of the moonlight in the shadows there to indicate form in the distant shapes before the clouds. It may just be my screen, but I'm having a hard time seeing the forms on that layer.
Since we're on the topic of that layer before the clouds, you could consider shifting that dark blue highlight more toward green a bit to give the subconscious an easier time understanding it's greenery you're describing and not just clouds in heavy shadow. It should be clear enough that it's not the latter, but it's still difficult to know for sure that it's the former (assuming it *is* indeed greenery you're describing there).
Hope that helps!