We should have a way to import arbitrary meshes from modeling programs into Visual. This will probably take the form of an orientable primitive with something like a "file" attribute.
The biggest problem with this is agreeing on a file format. Most good modelers are outside the price range of a lot of potential Visual users and have steep learning curves besides. Lowest-common-denominator formats like DXF lack important information about surface normals.
I can't address this without more input on what formats would be acceptable.