> More importantly is when lateral grip finally breaks there is no warning to the driver with a cocked wheel and gentle progression: it just lets go.

This honestly depends on the tires. A lot of performance tires lose grip very gradually. Don't know what tires the Model 3 comes with, but with a good set it shouldn't be an issue.

> As a counter-example Mazda have always engineered some body-roll into the Miata / MX-5 so that it's fun and communicative in corners.

I daily drive an MX-5 and the body roll drives me nuts. If you ever drive a modded Miata or an S2000/BRZ or a Porsche Cayman it'll be very apparent how their lack of body roll gives superior driving dynamics while still being very compliant. Not saying Miata is a boat, but it's overly wallow-y for a car of that size.