Sharing user-generated content (with AssetBundle)

I want users to be able to import 3D models into their scene. I can do this with a C# script like this one. Then I want the users to be able to share those models, but I want the load system to be fast. AssetBundle is made for efficient content distribution. However, the BuildPipeline class (the core of AssetBundle creation) exists only in the Editor. What I really want is to programmatically generate AssetBundles. I wonder if anyone has dealt with this. I can think of a few solutions, all of which seem difficult.

• Have a "review" step where a Dev takes the model and makes it into an AssetBundle in the editor every time someone shares something

• Put a copy of the Unity editor on the server to somehow do the same thing

• Reverse engineer AssetBundle serialization so that I can generate it with my own script

• Build my own efficient content distribution system (this might take a lot of engineering to make it as fast as AssetBundle distribution).