Unity has a great system for prefabbing game objects. The only problem is that if you nest a prefab inside another prefab, unity will inline the contents of the child prefab. Unity has nested prefabs in their version road map, but the ETA is unknown and hasn't been slotted since version 5.4. I have some game objects that I need to reuse. Each instance needs to be slightly different and has some custom parameters. I also need to embed these game objects into other game objects. Here is a simple, but nice work around that works for my needs.
http://framebunker.com/blog/poor-mans-nested-prefabs/
There are also several 3rd party solutions available on the asset store, but am not sure how well those work however.