Seems you have the concept down Mate.
The GWX4 project looked heavily towards this very idea.
Slim the demands on how the Game Engine uses files to improve preformance. Then improve 3D model files for the eye candy.
We looked at how many ships are in the Game and what parts of those ships are repeated. The numbers of same 3D models will blow your mind!
Lifeboats alone is crazy! 3 or 4 models would cover all the lifeboats alone.
Given the repeat 3D models in all the files? Can you see what type saveings could be done?