[P-hack]

software diff isn't much of a concern IMHO, it is a plus actually if you want better slip control (as compared to "posi" or "lockers" or "open only"). I would take a solid state differential over a mechanical one in an EV.

The space isn't a big concern either (as compared to an engine and trans), though I do wonder what if any advantage using smaller high speed geared(sprocketed) inboard motors in something like the FVT setup would be. The FVT, or the dolphin (which is basically a motorcycle setup) seem like the best unsprung options though, no matter how small the motor/rotor are.

What are the compromises in a smaller high speed motor vs something like the FVT?

Edit, aside from the obvious, since the FVT sized motors don't have gearing/sprockets, that is less moving parts to wear and one less efficiency drop. Though the possibility of adding additional gears is reduced too.