Back then I had an A500 and was getting into PCs and had a lot of the early sound cards.
To me the real thing about Amiga Paula sound is that it sounded crisp (for 8 bit sound), not like you are talking to someone on the phone long distance like the Creative Sandblaster 1.0. It offered multiple sound channels in stereo, low CPU overhead... It was hard to beat, for a long time, but there is nothing really that much distinctive about it. Its more down to the sound samples and talent of the people that wrote the software and composed the tunes...
I would not be able to tell the difference between my Minimig 1.1 and my A1200 as far as sound, so if I really wanted a Paula Midi synth, using the real chip(like SidStation) would be foolish.
I'd simply do a new PCB based on Mimimig with a built-in midi port. Perhaps you could do it as an expansion to Chameleon 64, although I know less about that device.