I'd suggest for the interior sides of the ruined bricks to use something like rock instead of the brick texture. The brick texture implies that the brick was actually made that way instead of broken off.
Very nice work Tweetytunes! May I suggest on the parts where the brick has fallen off that you give it a staggered look. I noticed the brick in the real photos have that feature. Yor brick looks too smooth on those areas.
I stuck on what to do with the ground for this project.
Do I go for total rubble and debris on the ground as if it just happened or do I have it so its been a ruin for a few years and the area has been cleaned up - more like a tourist attraction like Grease `s temple.
Have gotten parts of the roof and some of the pilers done but not uv mapped, textured or rendered.
I would go for a decayed floor, a floor that is partially buried under rubble,ground and grass.
I think if you use a combination of those it will make it more believeable.
Like in the image you posted her that says 2005 bartellonline.com, i would only try to use a bit more contrast than in the picture