Spent a while removing a bunch of now unneccessary wiring and electrical components. Also deepened my hate towards electrical tape which turns into nasty sticky mess quite fast. I'll probably remove most if not all of it and use some spiral wire wrap instead when putting everything back together. I could have removed even more wires, but decided to spare some in case I could use some of the leads and connectors for controlling the electronics later.
I've also pretty much abandoned the 18650 battery idea due to enclosure challenges and also low C rating of the cells. 10 A just go too far without many many cells in parallel. Instead trying to decide between prismatics from CALB or Thundersky and cylindrical cells from Headway. We'll see. In any case the initial installation will probably use old UPS AGM batteries as originally planned.
Also still mulling over the motor. The Enertrac MHM602 is quite tempting. No chain would be lovely. On the other hand, ME0709 is cheap and ME1003 gives almost the same power while still being cheaper than MHM602, albeit more expensive than ME0709. Waiting for reply on my latest inquiry form Enertrac to see if it would make sense to get the rim and spokes locally.