There is a nice balance between polygon count and detail. For this particular scene I've decided on a poly budget of around 200k. That should be sufficient for everything, and will insure that the models will perform well on the current generation of hardware where total polygon counts for an entire view are kept somewhere between 400 and 500k. Materials are kept as cheap as possible, and models are made with Unreal Engine's poly reduction in mind for LODs. Currently the scene is sitting around 100k, and poly reduction looks pretty good at 50%. I've got plenty of room for additions while maintaining superior performance.
A post process volume was added in order to simulate the lighting which will be present in the project at the end. Lighting will no doubt be tweaked, but it is a start.
Below are some screenshots. Click to enlarge.