Mass effect style large structures with small details on the cheap?

I’m a programmer, so I want to do things efficiently and I saw that Mass effect did some sort of kitbashing for their level designs.

Has anyone got any hints for how to decide the scale of objects and texturing methods for them? I mean relating to how to get low detail large objects to sit nicely with high detail small objects in the same level.

A lot of mass effect models and textures were very low res, which allowed then to optimize the game for just about every pc/platform. The best way to get large and small objects to work together is trial and error. Try to incorporate some sort of detail texturing in the larger pieces so that they can hold up to close shots. Take a look at the level in the shooter game demo, it should give you an idea.