In my opinion, this is a massive, gaping hole in the Substance workflow. It is the one thing that has kept me from purchasing the whole Substance suite.
in Cinema 4d, you have to load your textures one at a time, from a list of file names, before you can see a preview. This is counter intuitive and super time consuming.
Substance Player is halfway there. But unfortunately, it has no organizational capabilities, does not allow import of 3rd party .sbsar, is not integrated into 3d platforms, and requires too much back and forth. Its disappointing, because its really good texture technology that is so much of a hassle to apply, its almost inaccessible.