While we certainly intend to use the space in the X for hauling stuff around, our main use will be as a medium range (overnight) cruiser for ourselves and another adult couple. With lots of interior room, upright seating, and great visibility, the X would be a far better cruiser than the S.
To that end, I'd like to see an option package that upgraded the middle seat traveling experience.
Split luxury seats for adults
Heated middle row seats
Usable cup holders
Full reclining seats
Ability to move seats all the way back to the rear seats to maximize leg room
Separately controlled front/reat climate control
I'd also like to see the air suspension capable of lowering a lot to give a low step over height for older and partially disabled passengers. The S does have this capability, but the X has a higher ground clearance, so it would have to lower more. The car should also allow the lowered height to be maintained during parking so you could lower the car when you arrive, and still have it lowered when you return.
It would also be nice if the air suspension, like the S, could be set to sport for when I'm alone, luxury for highway travel, and boonies for camping park roads.