OK, many thanks for the details, so the RH seems made from a cassette spider.....LH seems custom made with LH threads (perhaps using a 135mm Hub into 150mm dropouts)
Anyway all that make a lot of sense to me....that big motor weights a bit over a complete 3220 or 80-100 drive (4,7kg including final chain, freewheel, adapters and sprockets on mine) perfect to prove that even for powerful RC, should be the right time to try the "luke" way to put most of the weight in motor mass, rather than reduce single or twins faster and smaller motors.
With your setup should be neat and easy to try a belt stage..... silent, clean, maintenance free and safer than a chain, not the best for dirt maybe....but the motor Itself as is, wouldn't see any mud/wet terrain, I suppose.
Unfortunately, the wider ratio you can get with a centertrack belt is 3.68, not enough. but A double, slim, standard toothed belt setup with two drive pulleys on the shaft and 2 epoxed/bolted driven, on both rotor's sides is anyway an elegant option. Even ditching the pedals and using belts both sides of the motor. (just need a customized fixed/fixed Hub with 2 rotor mounts and a 12mm TA bearing assembly) Than mount both driven pulleys to adapters like your LH one, each side....It should be done I think.
With the swing-arm mounted motor no flex issues will affect a belt transmission...only, you need to find a solution to tension the belt (new slider extended dropouts and/or sliding motor mount)
Also, Seems that the 2 sprocket ratio (4.75) is close to the Motordia/wheeldia ratio that from my raw calc should be 5.6.....what a perfect friction drive monster
I'm sorry to pollute your thread with my Ideas for it.....the bike and the thread are yours, but are so cool, that have stimulated my imagination too much. Hope you'll be ok with that...
Looking forward to see next details, and action movies 8)
Make one, dusting a Cromo at similar Voltages, and you'll be my hero!!! (noway to compare any Hubmotor bike with your one....though).