I guess the question is how much they'd gain in acceleration/performance (and thus be able to give up on battery capacity) by making the overall vehicle smaller

I guess the question is how much they'd gain in acceleration/performance (and thus be able to give up on battery capacity) by making the overall vehicle smaller and (ex-battery) 200-300 pounds lighter, vs. how much space for battery they'd give up. I don't mind if the S4-replacement costs $60-80k (loaded) vs. $80-100k for a Model S. I'd also take a car which had the same general size and chassis as the Model S but with a larger, more-secure trunk at the cost of seating capacity. My dream car is a 2-seat coupe with a trunk the size of a compact pickup truck bed.