Everyone's been focused on the exterior, but I want to say a few things about the interior...
Lights. Lights. Lights.
I have never seen a warehouse that lacks a single light. So maybe try to explore that a bit.
It's also wayyy to empty to be considered a warehouse.
Even an abandoned warehouse would have several series of shelving left behind.
So, if that's the theme you're going for, maybe try to add some of that.
Lastly, I sorta said this earlier, but it really is extremely small for a warehouse.
Obviously that would require rebuilding the entire thing, but maybe for future reference try to take into consideration all of the things that would be included in an average warehouse, and compensate enough space to add it all.