OK, have now had model S for 5.5 years and model 3 for a little over 1 month. I drive the S 80% of the time. But every time I drive the 3, I am impressed by SOMETHING that Tesla must have learned... Anyhow, here's my starter list of improvements IN MY OPINION, and NOT in any particular order: 1) Homelink... signal a ton stronger, operation a lot more consistent. 2) Mirror dipping on reverse... just does it automatically, no need to program in dip setting. 3) Coat hooks... of course some are better than none, but they did it nicely by having them flush/pop-out 4) Door pockets/storage... again, some better than none, but they don't detract from clean look 5) Ventilation... I think the slot vent is genius. really works well, no vent covers to rattle and have to adjust... rear ventilation seems much stronger. 5) UI content organization.... I liked the S at first when it was driver configurable. Since it became half configurable (some apps claim top, menu bar disappears), it is unpredictable and much worse. I prefer just having everything dictated, easier to learn and remember, and the 3 does it well. 7) UI visibility... that screen is so bright and clear that it defies sunlight! 8) Microphone setup... it must be better. voice commands work. people don't complain they can't hear me on calls. 9) Forward visibility... amazing. like being on a motorbike. 10) The balance... the balance of power, responsiveness, steering, suspension, feedback, etc. is perfect for me... The S wins on pure grunt, but the 3 has that elusive balance that few cars have IMO. My first 2002, Boxster... still trying to think of another. Other dual Tesla owners, please nominate your own. For those who want to jump in and argue... please don't do it unless you have lived with both cars, and please don't make this about which car is better. They are both great and have their comparative virtues.