This is almost perfect, but I’d drop the opacity of the bottom shadow a little, as it’s currently quite harsh.

Thanks for commenting, it’s always awesome to see your work .

Your version is actually awesome. I don’t think it’s all that flat, but here are a couple of tips to step it up a level:

The bottom vignette fails to vary based on the backdrop behind it. This flattens your image a little, as these bottom shadows should really apply to the bottom surfaces, not just the flat canvas.

If you look at the large building in the left of the piece, yours is definitely flatter than the version in this tutorial. Try adding some stronger lighting, as your main light source is nearer the center. This means the right edge of the building should be well lit, but the left edge should be shadowed.

Try adding some mist/fog to the floor, as this is a great way to add more perspective and depth to your piece. This really makes it look less than a bunch of photos stuck together, and adds ATMOSPHERE, which is crucial to bringing everything together.