X3M I guess, first C2 need to have the tools to give you the way to get the .obj/.mtl correctly from the field and after that find some way to get the code and build the files or a way to create the mesh using that information.
I know this is not simple, in fact maybe is impossible but with the things i saw how all works is the unique way i found to do that, but in my opinion can give us a more flexible way to work and do things.
1
Imagine i share my own library, if somebody like all the models i have on it, for example 50, they only have to select all, copy and paste in their own project and they will be ready to use.
2
Now we have to import the files: Obj+Mat+Texture maps. That can be 5 or more files for each model that we will have to organize in the imported files tab. After that we will have to create 50 OBJ.objects in the C2 layout and one by one set the correct name of the .OBJ or .JS model imported.
Also with the different libraries of the people they can have repeated the model/material/texture names so in that case we will have to rename it to Stairs1.obj, Stairs2.obj, stairs2.mtl, stairs2.png etc... a thing we avoid in the other way because there is no .obj/.mtl/ textures names.
And for manage add/remove models. We have to remove the object in the C2 layout and search in the imported files the ones associated.