Ulco, this is the best model *I* have seen from you so far! Its got some great details.
I think damaging it would be cool, but not at all necessary. If you are going to portray the structure in its own time, it would not show damage from age, but it would still be filthy. The old world was disgusting, dirty filthy
But you have some dirt in there already and that looks real nice.
2 things...
It would be great, if you have the time and inclination, to also think about detailed human figures for the final composition. People would clarify scale perfectly! And also, I think that is the area of TG2 that has the least amount of topics. It would be nice to see some more ground broken on that subject.
And perhaps, rather than lots of mountains in the background, or any kind of big terrain, you could put some of you lower polly models in the background to form a village in the distance.
I have to say that I know TG2 is almost all about terrains, but the renderer is just so good and easy to use, it makes models look great!
I would also like to know more about your modeling in general.