The smaller diameter will lower your gearing so torque shouldn't be a problem so long as you can lace the hub into the rim.
Looks like the biggest problem might be overheating, what with slow speeds up hills and large loads.
Assuming these hub motors all have some kind of throttle instead of an auto-assist?
Hub motors can do PAS as well.
@M_A_X started
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Looks like the biggest problem might be overheating, what with slow speeds up hills and large loads.
Assuming these hub motors all have some kind of throttle instead of an auto-assist?