As OP of the thread decided to try and organize it a bit, as things keep getting re-hashed. I have divided the options mentioned in the thread into four categories, and loosley tried to order them with the most mentioned options being at the top of the category. If an option was only mentioned once, I might of skipped it, and probably missed some others altogether. Feel free to alter the list.
Interior
accessible drink/cup holdrs
heated seats
ventilated/cooled seats
ventilation/controls in the back/ 4 zone climate control
Removable second row seating
lay-flat cargo area.
Storage - more of it (compared to model s)
memory seated position for at least two drivers
Rear seat entertainment
heated steering wheel
Aux power front and rear
driver seat automatically goes back when turn car off, making ingress and egress easier
sun visors slide along (extends out on) an arm so that they can be positioned where the sun is when on the sides,
trunk partition
dog barrier
mini-refrigerator
Exterior
panoramic sunroof
roof rack with needs ability to hold kayak and skis
normal door option
memory mirror positions for 2 drivers with Electrally foldable auto-dimming heated side mirrors
tow hitch/wiring standard
good clearance without resorting to raising the car with air suspension
Luxury rear seating option for adults.
soft close doors
automatic trunk closure
lightweight multi-use trailer
different performance wheels than the ones currently on the model S
more aggressive/masculine appearance for the performance version
Aluminum package interior for the performance version
cargo liner as an option as well.
Battery and Charging
85 kWh and 100 kwh battery options
Dual plugs for the dual chargers so the car could be plugged into 2 240V charge cables simultaneously when alone at a charging station.
Option for charge-port on either side (since my wife and I will share an HPC (true love!)
Charge adapter for same connection to Roadster or vice-versa
Drive-In / camping mode
V2G / V2V2 charge support
Driver Assist
Adaptive cruise control
Parking assistance system (cameras, audio/visual sensors, etc)
blind spot indicator
Auto dimming high beam headlights
Lane Change Warning
Drowsy Warning
Crash detection and braking system
HUD
I also added another picture of the cargo partition, showing a recent trip to Costco for our family. It just makes things so much more accesible, especially if you have multiple stops and things to pick up. While Costco is not the norm for us, (in terms of how much groceries we buy at once) it serves as a great example of keeping things accesible ie. the stroller, when you have other things in your trunk space. When not in use you can lay it flat on floor of the cargo space. I really cannot beleive most SUV's do not have this and want more people to ask for it.