OIC.
Looking at the specs, sure looks quicker, but not really much more efficient. EPA suggests 47 MPGe, or 22 mpg combined:
https://www.fueleconomy.gov/feg/noframes/36709.shtml
15-20 mile all-electric range. If that range is sufficient for your daily driving, then you might be onto something.
Regarding the S6, I’m surprised that you find the headroom lacking, even at 6’ 5". I’m 6’ 2", but very long-waisted (32" inseam!) and it has plenty of headroom for me…