Much too shallow for my taste, and I mean that in every sense of the word.
I've seen enough of these typical ruin sceneries to wipe my arse clean if I printed them.
However, if I am to take a more constructive approach I would first emphasize that if we are to consider this as a foreground, you could dramatically increase the appeal by adding some depth to it (mountains, clouds, standard procedure really). Unless of course you want to go for an unexpected result, in which case... well, surpirse me.
Also, minor notion; to complement the very fine quality of the doodads you are using, try some matching tiles.