Here's what I've come up with, with some notes.
Ideas for unique mods:
JCM 900 SL-X (too close to 59RR/Mashall+?)
Sunn (might be hard to match tone)
Peavey XXX/JSX
Blackstar S1 (too marshall like?)
Carvin V3
Krank Rev (already covered by Stein and Kraken?)
Fortin (ripping off smaller boutique amp douchy?)
Kinda sorta rip off idea:
Crazy custom recto (active EQ, 2ch-3ch switch for fizz, rectifier on/off)
All things considered, the Recto idea would be easiest since the tone stack is pretty much in place, and we'd just be adding switches for the featues I listed and could add common/public tweaks (ie have a switch with two different caps attached to C3 as a tight switch). This assessment ignores the active EQ setup, which may not be possible to implement.
If we go from the first list, we'd have to research how to adapt the amp's tone stack and gain stages to a module, which might be a little much for us.
Surely I missed some amp no one else does or made a bad assumption, so ideas and critiques are welcome.