This is very good and wish you the best, though as this was M500/600 thread, what I, and I believe Ornias, were talking about was basically a 'drop-in' replacement for either the locked down OEM M500/600 controller or the 'unobtanium' Luna V2 controller. It would have to fit in the original M500/600 case which most likely means almost all surface mount components, likely a 4-layer PCB and an MCU which is likely going to be north of 50-60+ pins on a tiny chip.
I believe the VESC controller designs are all open source, too. Need to spend some time researching what is the latest/greatest/most recent revisions. But seems a good start would be looking to fit one of those deigns on a board shaped for the M motors.