I use the LP-16 essentially as a sound card with multiple outputs. I now have 18 audio outs for my virtual instrument(s). Of course, I also have more than 18 sets of amplifiers and speakers, and let the “air” do the mixing, though I tweak levels quite a bit. For live virtual instruments it is a more convincing arrangement than mixing it all down to two speakers. (More are always better.) I use this with a program much like Hauptwerk, but it runs on Java and is not limited to pipe organ sounds. That’s why it runs on PC, Apple, or Linux.
I prefer to do this in stages rather than buying a much more expensive device which also requires more expensive adapters like D-plug adapters, a new set of balanced cables, etc.
I am at the stage now where I’m dreaming/planning for the future, but I’m not entirely sure of what is even possible without spending many thousands of dollars.
I appreciate your time and patience.