Enable USB-C port for wired AA / CP.
Enabling wired Android Auto or CarPlay through the USB-C port would help in situations where wireless is unreliable due to interference. It would also expand the number of use cases with devices other than main phones, similar to the request for Miracast.
This would require a way of ensuring the cable entry did not compromise the port or SDcard slot such as a special waterproof boot stretchy enough to fit the head of a slim cable through.
Another use case would be adding extra functionality for something like a DAB+ USB Receiver Dongle, this would require a relatively simple app to run, separately to the phone.