Motors in the wheel is something I have on my mind for a long time now.
Simple out runners that are used for indoor rc planes. You do get more weight in the suspension, but the possibilities are endless.
Everything will be in software and be dynamic.
Differential can be done in software based on the servo angle input.
Overdrive and under drive (what used to be a bigger or smaller pully) can be done while accelerating or braking.
Also brake harder front or back, esp etc.
4 small escs (or 4 in one) with small gauge wire. Imagine how much freedom you have in the car that only needs to house the esc(s), battery and steering servo.