fietsbob,
I do get why you like IGH. They are super neat. But if I want a rear hub motor, there is just one IGH choice, the TDCM motor. It has a five speed Sturmey Archer, it's one of the most expensive choices out there, and it can't be changed. If it's not a wide enough spread of gears that's too bad, it is what it is.
By switching to a derailleur, I get many more options for gearing, and I get something familiar. And as I said, new motor skills don't come easy to me these days, so familiar is good. Plus, I can tell when the gears have changed by sound and by visual inspection, and having things I can see and hear is huge for me since I have such trouble telling what is happening by feel. When I was test riding it with the stock IGH I could barely discern when the gears had changed. IGH is too elegant for me. LOL!
With a derailleur I can get a hub motor with a freewheel or a cassette, both kinds are out there. But either uses the same derailleur. That's why I am here instead of in the electric sub forum or the adaptive/disability sub forum. I hope you guys will let me stay.
The pedal assist is controlled by either a cadence sensor or a torque sensing replacement bottom bracket. I won't subject you to that discussion here, that's one for the electric sub forum.