Very well put Bob. GM and BiaB go hand in hand and I hope that never changes. However PGMusic could do a little more to make GM sound a little better by using non-quantized backing tracks, much like what they call SuperMidiTracks, which are really just non-quantized tracks.

But as you said to get a more realistic sounding emulation you will need a much better sound source than GM and a little MIDI control knowledge.

YMMV

Whenever I get something stuck in the back of my throat, I dislodge it by drinking a beer.
It's called the Heineken Maneuver.

64 bit Win 10 Pro, the latest BiaB/RB, Roland Octa-Capture audio interface, a ton of software/hardware