Stack-ranked:
TACC chill-level adjustment (I'd like it even more chill on both acceleration and deceleration)*
Passenger-accessible audio mute
Cut steering power when the vehicle is placed in Park after driving
Entertainment improvements (Spotify in USA, USB fixes,...)
Operator hints replace map display in Valet mode (
reddit)
Blind spot alerting
Single touch to speak next direction even when directions muted (my 2002 Lexus has this, and it's surprisingly handy)
Associate driver settings with driver phone/card
Map travel-up setting should be sticky (rumored to be in 36.2?)
Self-park (perpendicular and parallel) without neighbor cars
Self-park (perpendicular and parallel) without pulling past
Adaptive (or just modulated, though adaptive would be better, and the hardware is clearly present to do this) brake light flash
Yellow rear turn signals
Map recenters above audio controls when audio controls up
Ability to default audio off regardless of previous audio state
Aerial view for parking (even if it's got a dead zone in front; care more about sides)
Navigation waypoints
Set TACC to current speed even when below limit
Hands free EAP via selfie-cam
Voice command expansion (HVAC, audio, ...)
Text message support for reading incoming messages and dictating new ones
More restrictive valet mode
More sensitive automatic volume
Web browser