this is amazing work! kudos!! it sounds great.
hope you don’t mind, but i forked the project on github and started making modifications:
[ https://github.com/catfact/DX7-Supercollider ]
so far i’ve just refactored the script into a class so you can easily make multiple instances* and manipulate them a little more cleanly, like so:
s = Server.default;
s.boot;
s.waitForBoot { Routine {
x = DX7Clone.new(s);
x.note(42, 90, 10002);
12.wait;
x.note(42, 0);
}.play; };
next i’d like to fix issue with auto-freeing the synth with DetectSilence. (i think a HPF before DetectSilence will do it; if there are big DC components that get clicked off, oh well.) for now i just extended the max note length from 10s to 24h 
also planning to optimize some stuff like the data file usage.
(*) ok, multiple instances are still a little bugged ATM…