[Andusciassus]

It looks really good, but still somewhat unfinshed to me. I think it's the colour you've chose to use.
It looks very...brown? and the whole pice looks rather uniform. I really think it would look better if the walls of the building were drybrushed with a few layers of graduatly ligther grays.
To make it look muddy and worn you just give the lwest part of the walls a few brown washes and maybe some small printed posters, like in Ash's bunker.
Then go over the graveled parts again with a very thin (ie wash) dark brown/black to tie it all together a bit more.

But as far as the modelling part goes it looks fantastic.