We haven't seem much improvement on the market since second gen ternary hit. All coming improvements will be very gradual.
Cars on the market already hit possible upper/lower weight, and size limits for the battery pack.
> Weight distribution
Any other than low, and centre?
> Software updates
Do you want to play videogames on your car? Will you pay few thousand dollars more for a UI skin update once a year?
> in-wheel motors
May be, but that will only work towards killing the differentiation even more, at least in the low end.