Add an option to manually initiate battery preconditioning for high speed charging.
In my home state of Tasmania, Australia, there are no Tesla Superchargers, but there are other third-party fast charging stations, including some new 350kW chargers. Unfortunately, because the Tesla Nav doesn't know about these third-party chargers, it doesn't know to begin preconditioning the battery for them, the way it does for Superchargers. Because of this, the car starts charging at a very slow rate, and takes a lot longer to charge than if it had preconditioned the battery.
It would be wonderful if Tesla could integrate awareness of third-party chargers into their system, but a very quick and simple fix until that happens would be a manual option on the touchscreen to prepare for high speed charging. To be honest I am quite surprised this ability is not already included - there are a lot of high speed but non-Tesla chargers in the world.